Syrian army tanks are seen in the Suleiman al-Halabi neighborhood after clashes between Free Syrian Army fighters and regime forces, in Aleppo city October 5, 2012. REUTERS/George Ourfalian

ISTANBUL (Reuters) - Turkey's prime minister said on Friday his country did not want war but warned Syria not to make a "fatal mistake" by testing its resolve, and its army retaliated for a third day running after more mortar rounds from Syria landed on its soil.

In a belligerent speech to a crowd in Istanbul, Turkish Prime Minister Tayyip Erdogan warned Syrian President Bashar al-Assad that Turkey would not shy away from war if provoked.

The speech followed a Syrian mortar barrage on a town in southeast Turkey that killed five people on Wednesday.

Turkish artillery bombarded Syrian military targets on Wednesday and Thursday in response, killing several Syrian soldiers, and the Turkish parliament authorized cross-border military action in the event of further aggression.

"We are not interested in war, but we're not far from war either. This nation has come to where it is today having gone through intercontinental wars," Erdogan said in his speech.

"Those who attempt to test Turkey's deterrence, its decisiveness, its capacity, I say here they are making a fatal mistake."

At least two mortar bombs fired from Syria landed in farmland in Turkey's southern Hatay province on Friday, one of them around 50 meters into Turkish territory, and a military unit responded immediately, Hatay Governor Celalettin Lekesiz was quoted as saying by the state-run Anatolian news agency.

A government official told Reuters there had been similar incidents over the past ten days due to intensifying skirmishes on the Syrian side of the border, and that the Turkish army had been responding in kind. But he said Wednesday's fatal strike on the town of Akcakale had been of a different magnitude.

"If there was gunfire, we returned the gunfire, if there was a shell we returned two or three shells, to warn them and deter them. Until Akcakale we were not very concerned that they were deliberate," the official said, asking not to be identified.

"Wednesday was different. There were five or six rounds into the same place. That's why we responded a couple of times, to warn and deter. To tell the (Syrian) military to leave. We think they've got the message and have pulled back from the area."

Turkish broadcaster NTV said Syria had given the order for its warplanes and helicopters not to enter an area within 10 km (six miles) of the Turkish border and had ordered its artillery units not to fire shells in areas close to the border.

There was no confirmation of this from the Syrian authorities.

At the United Nations, the Security Council condemned the original Syrian attack and demanded that such violations of international law stop immediately.

The United States has said it stands by its NATO ally's right to defend itself against aggression spilling over from Syria's war. Russia, a staunch ally of Syria, appealed to Turkey to stay calm and avoid any action that could increase tensions.

Russia said on Thursday it had received assurances from Damascus that the strike on Turkey had been a tragic accident but Erdogan dismissed it, saying this was the eighth time Syrian mortar rounds had hit Turkish ground.

REBELS SAY THEY CAPTURE AIR DEFENCE BASE

The cross-border violence was the most serious so far in the conflict, now in its 19th month, and underscored how it could flare across the region.

Turkey, once an Assad ally and now a leading voice in calls for him to quit, shelters more than 90,000 Syrian refugees in camps on its territory and has allowed rebel army leaders sanctuary.

There is little public appetite in Turkey for sustained military intervention in Syria, butgovernment ministers have struck a bellicose tone.

"If Turkey had been a country that was interested in going to war, when the plane was downed it could have used that as an excuse and flattened Syria," EU Affairs Minister Egemen Bagis was quoted as saying on Friday, referring to Turkey's restraint when Syria shot down a Turkish reconnaissance jet in June.

"Thankfully Turkey's military power today is at the point where it could destroy Syria within a few hours. But we don't have any problem with the Syrian people," Bagis was quoted as saying by the Radikal newspaper.

More than 30,000 people have been killed in the revolt against Assad, which began with peaceful street protests but is now a full-scale civil war also fought on sectarian lines.

Across the country about 180 people were killed in violence on Thursday, including 48 government soldiers, the British-based Syrian Observatory for Human Rights said.

The rebels said they had captured an air defense base with a cache of missiles outside Damascus on Thursday, a boost to their campaign after a series of setbacks in the capital.

Video posted on YouTube of the aftermath of the assault showed dozens of rebels dressed in army fatigues celebrating as black smoke rose from a military installation behind them.

A middle-aged man holding a rifle says the attack was carried out by a rebel battalion from the town of Douma. It also showed rebels at a weapons cache which included what appeared to be part of a surface-to-air missile.

It was not possible to independently verify the videos. Access to Syria for foreign journalists is restricted by the Syrian government.

Although fighting often takes place in the Damascus suburbs, rebel forces have been unable to hold areas for long in the face of government artillery and air power. They have staged devastating bomb attacks on government and military offices in the heart of the city, however.

The U.N. condemnation was issued after two days of negotiations on an initial text rejected by Russia.

Consensus within the council on Syria-related matters is unusual and it has been deadlocked over the conflict, with veto-wielding Russia and China rejecting calls to sanction the Damascus government.

(Additional reporting by Daren Butler in Istanbul and Ayat Basma in Beirut; Writing by Nick Tattersall and Oliver Holmes; Editing by Andrew Roche)

ANKARA, Turkey (AP) — Another mortar shell from Syriastruck Turkish territory on Saturday, prompting a fourth day of retaliatory artillery fire from Turkey, the state-runAnadolu Agency reported.

The mortar landed in a rural area near the village of Guvecci, during intense fighting between the forces of Syrian President Bashar Assad's regime and the rebels in Syria's Idlib province across the border. No one was hurt by the mortar. ButTurkish troops near Guvecci immediately responded with "counter-fire," the agency said.

The latest shelling came a day after Turkish Prime Minister Recep Tayyip Erdogan called on Syria not to test Turkey's "limits and determination."

Turkish artillery has been responding to shelling from Syria since Wednesday, when a mortar landed at a Turkish border town, killing five civilians.

Turkey's parliament on Thursday also voted to allow cross border military operations in Syria, further raising tensions between the neighbors that were once close allies.

Copied on the email was U.S. Ambassador Chris Stevens, who was killed in a terrorist attack on the diplomatic post in Benghazi, Libya, Sept. 11, 2012, along with three other Americans. That attack has prompted questions about whether the diplomatic personnel in that country were provided with adequate security support.

No one has yet to argue that the DC-3 would have definitively made a difference for the four Americans killed that night. The security team in question, after all, left Libya in August.

But the question - both for the State Department, which is conducting an internal investigation, and the House Oversight and Government Reform Committee, which is holding hearings next week - is whether officials in Washington, D.C., specifically at the State Department, were as aware as they should have been about the deteriorating security situation in Libya, and whether officials were doing everything they could to protect Americans in that country.

Earlier this week, the chair of the House Oversight Committee, Rep. Darrell Issa, R-Calif., and another member of the committee wrote to Secretary of State Hillary Clinton listing 13 incidents leading up to the attack, ranging from IED and RPG attacks to a "posting on a pro-Gaddafi Facebook page" publicizing early morning runs taken by the late Ambassador Stevens and his security detail around Tripoli.

"Was State Department headquarters in Washington aware of all the above incidents?" they asked Secretary Clinton, requesting written responses by Oct. 8. "If not, why not? If so, what measures did the State Department take to match the level of security provided to the U.S. Mission in Libya to the level of threat?"

The subject line of the email, from Miki Rankin, the post management officer for Libya and Saudi Arabia, reads "Termination of Tripoli DC-3 Support."

Rankin informs Stevens and the others on the email, whose names have been redacted, that Undersecretary of State for Management Patrick Kennedy "has determined that support for Embassy Tripoli using the DC-3 will be terminated immediately. Post's request to continue use of the plane in support of the SST was considered. However, it was decided that, if needed, NEA will charter a special flight for their departure."

You can read the email HERE.

An "SST" is a Security Support Team, about 16 Special Forces troops assigned to protect officials from the U.S. State Department. This particular SST was assigned to the U.S. Embassy in Tripoli.

Shown the email uncovered by ABC News, a spokesman for the committee said the "document is consistent with what the Oversight Committee has been told by individuals who worked in Libya. Ambassador Stevens and the diplomatic mission in Libya made multiple security related requests that were turned down by Washington based officials. Security related transportation has been identified as one of the particular items where embassy personnel did not receive the support they sought."

Provided with a copy of the e-mail, a senior State Department official downplayed the importance of the denied request. The official told ABC News that "the DC-3 was pulled from Iraq and moved to support Libya early on when there was no commercial airline service into Libya. When commercial service was re-established in Libya, the aircraft was reassigned to other State Department business. We use our aircraft when no commercial flights exist."

The U.S. government official who provided the email to ABC News - and wanted to remain anonymous because of the sensitivity of the matter - described the small DC-3 plane as an asset for a security team to more freely and safely move throughout the country, and to more easily transport arms and other security equipment. In short, having the plane allowed the security team to better perform its duties, the official said.

The State Department official acknowledged that the plane was used to get around Libya, not just to get in and out of the country. But once commercial air service was re-established, the State Department decided that the SST didn't need the plane anymore. The security team, it would seem, disagreed.

Told of the State Department's explanation, the House Oversight Committee spokesman said the "State Department's naive determination to follow rigid bureaucratic policies, instead of making common sense decisions that took the serious threat of terrorism conveyed by those on the ground into account, appears to have been a significant factor in the Benghazi Consulate's lack of preparedness."

On Wednesday, Oct. 10, the committee will hold a hearing featuring the testimony of Regional Security Officer Eric Nordstrom, who was stationed in Libya from September 2011 through June 2012; and Deputy Assistant Secretary of International Programs Charlene Lamb.