With 79 people already declared dead, 11 in intensive care and dozens missing, the apparently arson fires sweeping seaside regions of Greece will almost certainly surpass the 84 killed in 2007, which also destroyed two million olive trees and burned 670,000 acres of forest and farmland.

The fires were in the Attica region outside Athens and appeared to be set, Citizens Protection Minister Nikos Toskas said, a common act so that developers can later build on the land as there’s law against doing so once it’s cleared, and with frequent unlawful construction, particularly along the seaside. The government allows it if people pay a fine.

The fires struck two coastal resorts popular with vacationers from Greece’s capital and caused at least 187 injuries, including 23 children, a fire department spokeswoman said in televised comments.

The fires are worse than in 2007, when record-high temperatures led to a series of blazes across the country. This week’s fires concentrated around Mati, a coastal settlement in northeast Attica, and were stoked by heavy winds, which spread the flames in the dry conditions, but there were others, including the beach area around Kineta along the national highway in Corinthos.

“Greece is going through one of its hardest moments,” Prime Minister Alexis Tsipras said in a televised address, declaring a three-day period of national mourning. “Today Greece is in mourning, but we cannot allow grief to overcome us.”

Other countries were sending help for overwhelmed Greek firefighters, including 60 from Cyprus, two water-bombing planes from Spain, the fire department’s spokeswoman said. “Europe will stand by our Greek friends in these difficult times. Help is on its way from several EU countries,” European Council President Donald Tusk said in a tweet.

The government held an emergency meeting on Tuesday to discuss the situation and organize compensation for damages but no word yet on trying to find out if any of the fires were set and who was behind it.

Tsipras spoke by phone with European Commission President Jean-Claude Juncker and got a pledge for whatever help is needed.