BEJAR, SPAIN (AP) — Hundreds of firefighters backed by helicopters and fixed-wing aircraft struggled Saturday to contain one of Spain’s deadliest wildfires that killed a least 12 people.

A combination of light winds and high humidity are helping crews but the sheer size of the fire still poses challenges, Antonio Sanz, head of Andalusia’s emergency services, said. The fire has scorched some 66 square kilometers (25 square miles) of forest and farmland, about the size of Manhattan.