ATHENS – With crews still going house-to-house looking for more victims of the Greek wildfires that killed at least 83 people, US military drones based in the country, along with Greek surveillance, showed there were multiple points of origin, indicting they were the works of arsonists.

That’s a common tactic used to clear land for development with no law against building on burned land despite years of summer fires that have killed hundreds of people but have been profitable for developers after the forests and woodland and bodies were cleared.

Defense Minister Minister Panos Kammenos said the US, with American Navy reconnaissance and patrol aircraft also assisted in the firefighting effort and were gathering footage to try to determine whether the fires had been set, although government spokesman said “Fifteen fires were started simultaneously on three different fronts in Athens,” to accelerate the blazes in different areas, including north of Athens in the seaside area of Mati, 98 percent destroyed, and west of the Capital in the beach area of Kineta.

Arsonists frequently target forests around the capital to try to clear more land for development but there have been few arrests or prosecutions despite repeated claims of outrage by successive governments and with the response to this year’s fire being slammed for being slow – reports said it took firefighters an hour to get to the Kineta blaze – and with no evacuation or disaster preparedness plans.

Greek anti-terrorist police were also investigating whether the fires were set, an unidentified source told the news agency Reuters.

A U.S. government official said MQ-9A Reaper drones had been used in the effort, along with U.S. Navy VP-10 and P-8A reconnaissance and patrol aircraft. The official asked not to be identified because details of the U.S. assistance had not yet been formally announced, the Associated Press said.

Kammenos said the footage from the Greek and U.S. surveillance aircraft would be analyzed along with satellite images, and that preliminary findings suggested that the fire started at multiple points, which would now be examined on the ground.

Joint police and military patrols have been sent to the fire-stricken areas to deter looters and monitor nearby areas for potential arson attacks, he said.

“We will forward our findings to the Fire Service because they are ultimately responsible for the investigation,” Kammenos said.

“But this had such tremendous force, powered by winds up to 110 kilometers per hours. … It jumped over a road as wide as a highway. When you have conditions like this, nothing can stop it.”