Four separate wildfire fronts continued to rage in southern Greece on Sunday morning, with the official death toll rising to 52 in the wake of an unprecedented barrage of fires that erupted since Thursday, fanned by gale-force winds, heat and amid widespread speculation of arson.

The most threatening blazes were centred in the southwest Peloponnese, the hardest hit area so far; in two districts in southern Evia island, Aliveri and Styra, as well as southeast of Athens proper at the suburban Kalyvia township.

An undetermined number of people are unaccounted for, authorities said, saying fears of an even higher death toll, while dozens of individuals, mostly in the southern Peloponnese, were hospitalised. Thousands of hectares of crops, pasture land and forests were scorched.

Fire-fighters looked to weaker winds and assistance from a half dozen neighbouring and west European countries -- in the form of fire-fighting aircraft -- as allies on Sunday in the battle to contain the flames.

In the wake of the unprecedented natural catastrophe, Prime Minister Costas Karamanlis on Saturday evening declared a nationwide state of emergency and promised hefty financial assistance for fire-ravaged victims and regions.

In expressing his personal "grief and rage" over the wildfires, Karamanlis also stressed that: " am angered, as are all Greeks, by the fact that so many wildfires occurred in so many different parts. This is not a coincidence."

Caption: ANA-MPA file photo of PM Costas Karamanlis.