Two eastern Oregon ranchers convicted of arson on federal land turned themselves in to a California prison this afternoon, as militia members -- who say the ranchers are going to jail for a crime they did not commit -- continue an armed occupation of a wildlife refuge in the state that's on federal property.

Dwight Hammond Jr., 74, and his son, Steven Hammond, 46, were convicted three years ago of setting fires in 2001 and 2006 on lands managed by the U.S. Bureau of Land Management, "on which the Hammonds had grazing rights leased to them for their cattle operation," according to the U.S. Attorney’s Office.

After a years-long legal battle, the Hammonds turned themselves in today at Terminal Island in San Pedro, California, at about 5 p.m. ET.

Arson on federal land carries a five-year mandatory minimum sentence, but the Hammonds argued that the rule was unconstitutional.

While a trial court "imposed sentences well below what the law required based upon the jury’s verdicts," according to the U.S. Attorney's Office, the Ninth Circuit Court of Appeals upheld the federal law, calling the sentence "not grossly disproportionate to the offense."

The Hammonds' five-year prison terms were imposed in October 2015, with credit for time they already served.

After a rally for the Hammonds on Saturday, armed militia, including sons of Cliven Bundy -- who was involved in a standoff with the government over grazing rights in Nevada in 2014 -- initiated the occupation of the headquarters of the Malheur National Wildlife Refuge.

Ammon Bundy, one of those sons, called the earlier rally successful, but said Sunday of the Wildlife Refuge standoff, "If we do not make a hard stand, we will be in a position where we won't be able to as a people."

Harney County Sheriff's David Ward's message to the occupiers today: "It's time for you to leave our community."

He asked them to end the occupation peacefully now that the Hammonds have turned themselves in.

Ward said what began as a peaceful protest took "an unfortunate turn when some of those folks broke off and began an armed occupation."

Bundy said today the occupying group is called "Citizens for Constitutional Freedom" and its purpose is to "restore and defend the Constitution."

He said he came to the Burns, Oregon, area about eight weeks ago and met with the Hammonds "many, many times."

"I watched them in tears multiple times," he said.

Rick Bowmer/AP Photo

Bundy today called the Hammonds a "good ranching family" and said they are going to prison for a crime they did not commit.

Attorneys for the Hammonds told ABC News in a statement earlier today, that, "as the Hammonds have previously stated, they will be reporting to the United States Bureau of Prisons today to serve their sentences."

"Dwight and Steven Hammond respect the rule of law," the statement continues. "They have litigated this matter within the federal courts for over five years and, in every instance, have followed the order of the court without incident or violation. That includes serving the entire sentences imposed in this case by the judge who heard the evidence at trial and who concluded that imposition of a five-year sentence under these circumstances would 'shock the conscience.'"

"The Hammonds will continue their legal efforts to renew their grazing permits," the attorneys say. "They will also pursue Executive Clemency. We hope that President Obama will agree with us and with the veteran judge who presided over the trial that the mandatory five-year minimum sentence is far too long for these ranchers."

Karyn Gallen, the niece of Dwight Hammond and cousin of Steven Hammond, said today that the occupation "is in no way connected to the Hammond family."

"The Hammonds have always been about family first," Gallen said. "I think it's important for Harney County ... to show support, but it has always been the request of the family to keep that peaceful."

Bundy told ABC News earlier today that, while he does not speak for the Hammonds, "We have spoken many, many times, and we understand each other on this issue."

"The Hammonds are only going to jail because they just feel there's nothing else for them to do," Bundy said. "But they very well know that this is wrong, along with all their neighbors and the other ranchers in the area."

White House Press Secretary Josh Earnest said President Obama is aware of the refuge standoff, but said it is a “local law enforcement matter” despite the fact that it involves federal land.

“This ultimately is a local law enforcement matter. The FBI is monitoring the situation and offering support to the local law enforcement officials as they try to deal with that,” Earnest said in today’s White House briefing.

“We’re hopeful that that situation can be resolved peacefully without any violence,” he said.

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ANKARA, Turkey (AP) — At least 21 migrants drowned off Turkey on Tuesday after their boats overturned in rough waters in two separate incidents as they tried to reach the Greek island of Lesbos, authorities and news reports said.

Nine bodies washed up on a beach in the resort town of Ayvalik early in the morning, prompting authorities to dispatch coast guard boats and gendarmerie officials to search the area by sea and by land for possible survivors. By late morning, the death toll reached 14, the coast guard said, adding that seven other migrants were either rescued or found alive.

Hours later, the private Dogan news agency reported that seven other bodies had washed up on shore at Dikili, a resort about 50 kilometers (30 miles) south of Ayvalik, the victims of a second migrant tragedy. The dead included women and children, the agency said.

Around 850,000 migrants and refugees crossed into Greece last year, paying smuggling gangs to ferry them over from Turkey in frail boats. Hundreds have lost their lives during the crossings.

The International Organization for Migration estimates that 3,771 migrants overall have died while trying to cross the Mediterranean Sea to Europe last year. The final number for 2015, released on Tuesday, was up from the 3,692 figure the agency released before Christmas.

The IOM said last year was the deadliest on record for migrants crossing the Mediterranean, with the number of deaths rising from 3,279 in 2014. The IOM said a large majority of the deaths last year were still on the central Mediterranean route, mainly involving people crossing from Libya — 2,892, or 77 percent. However, there were 805 deaths in the eastern Mediterranean — accounting for 21 percent of the total, up from only 1 percent the previous year — as that route became more popular.

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A Turkish rescue worker looks at the body of a migrant lying on the beach in Ayvalik, Turkey, Tuesda …

Top officials from Denmark, Sweden and Germany, meanwhile, were scheduled to hold talks in Brussels on Wednesday amid concern about new border control measures aimed at stopping migrants entering northern Europe, EU officials said Tuesday.

Sweden introduced ID checks on all people traveling to Denmark, and Denmark tightened border controls on its border with Germany on Monday for at least 10 days, citing concerns about public security because of migrant movements and border measures taken by other EU member states.

Danish officials said 18 people without proper ID were refused entry from Germany in the first 12 hours of the increased border crossing checks. Three people were also arrested, suspected of human smuggling.

In Turkey, Namik Kemal Nazli, the local administrator for Ayvalik, told the state-run Anadolu Agency that the victims of the first incident are believed to be from Iraq, Algeria and Syria. There was no information on the nationalities of those drowned in the second incident.

Nazli said were still searching for more migrants and that the death toll could rise further.

A body with a lifejacket was pulled from the sea onto the beach at Ayvalik by a fisherman and a military police official, Dogan news agency video footage showed. Other bodies, also in lifejackets, were seen lying nearby.

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Geir Moulson in Berlin and Jan M. Olsen in Copenhagen, Denmark, contributed to this report.

Latakia (Syria) (AFP) - In the windows of his father's shop in coastal Syria, Ihab replaces bottles of the national tipple arak with vodka, hoping to please his growing customer base of Russian soldiers.

"In the past the demand was more for whisky and arak, but with the Russians arriving in Syria, it's changed to vodka," Ihab, 32, says inside the "Crown" store in Latakia province.

"So I put these bottles in the front so they can grab them first," he says with a smile.

Ihab's storefront is one of many shops and restaurants hoping to attract the Russian soldiers who have arrived in Latakia since Moscow began a military intervention in Syria in late September.

Russia has stood firmly by its longtime ally President Bashar al-Assad since an uprising against his regime began in March 2011, providing political and military support to a government that has become an international pariah.

On September 30, Moscow began air strikes in support of the government, dispatching warplanes and several thousand servicemen to Syria, according to Russian officials.

The planes and soldiers are based at the Hmeimim military airport deep in Assad's heartland, south of the provincial capital of Latakia.

Russian soldiers go into the city for food, drink and entertainment, creating a new customer base with different demands for Latakia's businesses.

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'Cafe Moscow' in the Syrian coastal city of Latakia, where Russian customers drink for free …

To make what he calls his "new friends" feel comfortable, Ihab has begun learning a few Russian words from his father.

- 'Sales are up' -

"The Russians are a profitable economic presence, and our sales have gone up more than 20 percent since they don't argue about prices," Ihab says.

Russia's ties with Syria go back decades, with Moscow long maintaining a naval facility in the coastal town of Tartus.

Many Syrian military officers have trained in Russia, and it is not uncommon to find Syrians married to Russians or who speak the language.

Elsewhere in Latakia, Mohammad is arranging a display of camouflage jackets in "Commandos", a shop that sells military-style clothing and accessories.

The 26-year-old employee says sales are up and he now has more Russian customers than Syrians.

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Ihab stocks the shelves of his father's shop with vodka to please his growing customer base of R …

Pocket-sized portraits of Assad -- stacked next to boxes of combat boots under a large Russian flag on the wall -- are in particularly "high demand by Russian soldiers", he says.

Mohammad is also learning some Russian words and is pleased to see Russian soldiers learning Arabic words such as "salam", which means "peace" and is used for both hello and goodbye.

"They've become our friends," he says. "They pass by to say hello or they wave at me from afar as they pass by the place."

Haidar, 29, is so enthusiastic about the Russian presence that he has named the restaurant he opened last month "Russia".

"I've loved Russia and Russians since my childhood, and now is the time to express my love for them through my restaurant," he says.

The Russian flag billows in the breeze outside and the walls inside are covered with Russian sayings.

"Spasiba, spasiba," he calls out to his customers with a wide smile as they leave the restaurant. "Thank you, thank you."

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'Moscow Cafe' owner in the Syrian coastal city of Latakia, where Russian clients drink for f …

- On the house -

Haidar has hired a Russian language professor to teach his staff how to communicate with their new guests and hopes to find a chef who can make dishes for an all-Russian menu to please his new customers.

"The Russians have revived both the nightlife and daytime businesses," Haidar says.

But a Syrian soldier sitting nearby says the fuss over the Russians is "exaggerated".

"The whole world is focusing on the Russian army and has forgotten all about the Syrian army," he says. "We have been fighting for nearly five years and I haven't seen a single place called 'Syria' or 'The Syrian Army'."

And not everyone in Latakia's business community sees the Russians as paying customers.

Tarek Shaabo, 30, says he opened his coffee shop -- Moscow Cafe -- in 2012 as a sign of gratitude to Russia for vetoing UN Security Council resolutions on Syria's war.

"Since then, I swore to myself I would never let a Russian customer pay," he says.

When he first opened, only a few Russian military advisers would come to the shop, but now he says he serves Russians "nearly every day".

Another coffee shop nearby offers Russians drinks at half price, but at Moscow Cafe they are free.

"They came to defend us," Shaabo says. "The least I can do is host them in my small cafe."

He lights a cigarette using a lighter emblazoned with the Russian army's logo and extends an invitation to President Vladimir Putin, fondly nicknamed by some Syrians as "Abu Ali".

"Tell Abu Ali Putin he's got a place to stay in Latakia... Moscow Cafe is his home."

Tokyo (AFP) - Japan will send a huge cache of plutonium -- enough to produce 50 nuclear bombs -- to the United States as part of a deal to return the material that was used for research, reports and officials said Tuesday.

The plutonium stockpile, provided by the US, Britain and France decades ago, has caused some disquiet given that Japan has said it has the ability to produce a nuclear weapon even if it chooses not to.

Some 331 kilograms (730 pounds) of the highly fissionable material will be sent by ship to a nuclear facility in South Carolina by the end of March, Kyodo News reported Monday in a dispatch from Washington that cited unnamed Japanese government sources.

The shipment, which comes ahead of a nuclear security summit in Washington in March, is meant to underscore both countries' commitment to nuclear non-proliferation and is part of a deal they made in 2014.

It will be one of Japan's most significant overseas movements of plutonium since it transported one tonne from France in 1993 to be used in nuclear reactor experiments.

That shipment triggered an outcry at the time from countries citing environmental and security concerns.

A Japanese official confirmed the amount of plutonium to be sent to the US and said that preparations for the shipment are under way.

"But we can't comment on further details, including the departure date and route, for security reasons," the official in the nuclear technology section at the education ministry told AFP Tuesday.

The material has been stored at the Nuclear Science Research Institute northeast of Tokyo, he added.

Japan relies heavily on nuclear technology for its energy needs.

In 2006, then foreign minister Taro Aso sparked panic in neighbouring countries by saying Japan, a scientific superpower with numerous Nobel prizes to its credit, had the know-how to produce nuclear arms but opts not to.

Japan is the only country to ever have been attacked with nuclear weapons, and under a 1967 policy it refuses to produce, possess or allow nuclear weapons on its soil.

But in 2010 Tokyo admitted to previous secret agreements with the United States to allow American warships to carry nuclear weapons across Japanese territory and to take the arms to US bases on Okinawa island in an emergency.

US atomic bombs obliterated the Japanese cities of Hiroshima and Nagasaki in the closing days of World War II, killing more than 210,000 people.