Greek politicians reacted angrily on Monday following the admission by former Turkish Prime Minister Mesut Yilmaz that Turkish secret agents intentionally started forest fires in Greece in the 1990s as part of state-sponsored sabotage.

The claims are not new and were common knowledge on the islands of the eastern Aegean which were particularly hard hit by wildfires in the 1990s. But Yilmaz’s comments -- part of an interview published in the Turkish daily newspaper Birgun over the weekend -- are the first admission by an official source that Ankara was funding subversive activities in Greece.

According to Yilmaz, who served as premier three times in the 1990s, agents of the Turkish secret service set fire to Greek forests during the leadership of his archrival Tansu Ciller, from 1995 to 1998. During that period major forest fires caused huge damage on the islands of the eastern Aegean and in Macedonia.

The news sparked political outrage Greece on Monday. Foreign Ministry spokesman Grigoris Delavekouras said the claims were “serious and must be investigated,” adding that Athens was awaiting a briefing from Ankara.

Conservative New Democracy’s shadow foreign minister Panos Panayiotopoulos said the revelations “cast heavy shadows over Greek-Turkish relations” and called on Turkey recompense Greece for losses incurred.

Giorgos Karatzaferis, the leader of the right-wing Popular Orthodox Rally (LAOS), was indignant and triumphant, noting that he had been accused of extremism when as an MP he had accused Turkish secret agents of arson in Greece. “Now, from the lips of former Turkish premier, we have an admission to the crime,” he said.