The opposition leader, Giorgos Papandreou, said the government had been "totally incompetent" in fighting the blazes that continued to rage across the country after five days.

Today the body of a shepherd was found near Zaharo in the western Peloponnese.

"This government was proven to be totally incompetent, unable to handle the fire crisis, like all the other crises it encountered in its four-year administration," Mr Papandreou said.

Today, new fires continued to start quicker than firefighters could extinguish existing ones, leaving behind a blackened landscape of burnt forests, charred animal corpses and gutted buildings.

The government - which declared a state of emergency over the weekend - said the fires might have been caused by arson and several people had been arrested.

The prime minister, Costas Karamanlis, said on Saturday it could not be coincidence that so many fires broke out simultaneously in so many areas of the country.

Yesterday, senior officials hinted they believed the fires were the work of forces trying to discredit the centre-right government ahead of early general elections on September 16.

Mr Papandreou denounced the claims as baseless conspiracy theories, although across the political spectrum there was agreement that arson may have been involved.

Greece, unlike its EU partners, lacks a land registry and proper forest maps, and this is often exploited by unscrupulous developers who build on land after it is illegally burned and cleared. The public order ministry announced yesterday that a public prosecutor would investigate whether arsonists could be prosecuted under Greece's draconian anti-terrorism and organised crime laws.

Fire officials today counted 56 outbreaks since yesterday, with the most serious concentrated in the mountains of the Peloponnese in the south and on the island of Evia north of Athens.

Firefighters from 17 countries have been drafted in to help, with a group of 55 from Israel tackling one of the biggest fronts - in Krestena, near Ancient Olympia.

The daily paper Eleftherotypia led with the one-word headline "Incompetent" and accused the government of inventing an organised arson theory to cover its inability to deal with the crisis.

"The government invented the scenario of a 'disproportionate threat' to justify its incompetence, the dramatic lack of coordination and complete disorganisation of the state," ran an editorial.

Nearly a third of a billion euros has been set aside for immediate relief, although the finance ministry said the final bill was expected to be much higher.

According to conservative estimates, 110 villages have been razed, 2.5m hectares (6.2m acres) of farmland consumed and vast tracts of pine forest and olive grove incinerated.

Much of Arcadia - a prime tourist attraction in the central Peloponnese - has been left a moonscape. Thousands of rural Greeks fear financial ruin.

With the extent of the devastation becoming ever more evident, furious Greeks accused the authorities of incompetence. Many said entire swaths of rural Greece, now dotted with the charred remains of homes, cars and animals, had become uninhabitable.

Yesterday, authorities said more than 3,000 people had been made homeless by the blazes. Churches, schools and campsites had been turned into emergency centres, dispensing food, blankets and medicines.

Although some fires were brought under control, gale-force winds and high temperatures meant that new ones were constantly erupting, officials said. Firefighters were stretched to the limit, despite the 9,000-strong force being replenished by new arrivals from Israel.

Opposition politicians accused the government of failing to adequately coordinate efforts despite receiving aid from the European Union and other countries. With the carcasses of thousands of animals piling up across the countryside, there was also concern that epidemics might break out.

"The government has proven tragically incapable of dealing with fires," said Giorgos Papandreou, who heads the main opposition party, Pasok. "It could not save people's lives, property and homes ... it's time for Greek people to choose a strong government that can guarantee security, confidence and hope," he added, referring to the general election on September 16.

Before calling the election, six months early, Mr Karamanlis's New Democracy party had enjoyed a comfortable lead in the polls. But yesterday, as the fallout from the fires grew, the conservatives' lead had slipped to below 1 percentage point.