Aug. 2 (UPI) — Two firefighting helicopters collided midair as they battled wildfires in Greece on Sunday, killing two people.

A Danish pilot and a Greek crew member died in the crash while attempting to put out a fire in Porto Germeno, a seaside village northwest of Athens, officials said.

Two other crew members were rescued alive.

“I express my deep sorrow for the tragic accident involving the two decommissioned firefighting helicopters that claimed the lives of two frontline fighters in the war against fires under very adverse weather conditions — especially for our air forces,” Greek Prime Minister Kyriakos Mitsotakis said in a statement.

Three other firefighters lost their lives in the line of duty on Wednesday, as extreme heat continues to fuel deadly fires across southern Europe.

“These have been extremely difficult days for our country, with severe weather conditions and winds reaching as high as Force 10 on the Beaufort scale in many areas,” the prime minister said. “These conditions have tested — and continue to test — the endurance of the Fire Service, Civil Protection, local authorities, and the citizens themselves.”

Greek officials have evacuated hundreds of people as wildfires continue to spread throughout western Attica.

More than 16,000 acres have been burned by multiple fires on the Gulf of Corinth, The Daily Telegraph reported.