ATHENS, Greece — Wildfires intensified across southern Europe on Wednesday with a round-the-clock battle to protect the perimeter of Greece’s third-largest city and at least three deaths reported in Spain, Turkey and Albania.

Hundreds of firefighters battled to put out wildfires across southern Europe on Thursday, some of which are believed to have been set deliberately by arsonists and stoked by an extended heat wave gripping the region.

Wildfires intensified across southern Europe Wednesday, with a round-the-clock battle to protect the perimeter of Greece's third-largest city and at least three deaths reported in Spain, Turkey and Al