A fire broke out in a vent at the Eagle Rock Apartments on New Chalet Drive in Mohegan Lake, damaging four apartment units on Monday.
The Mohegan Volunteer Fire Association responded to the scene, finding the fire in one of the apartment's cockloft void space.
Nearby departments from Mahopac Falls and Putnam Valley assisted in putting out the flames.
There was significant damage to one of the units. The ceiling was torn off, and the area was left blackened.
The three other units in the complex suffered only minimal damage.
The Mohegan Volunteer Fire Association has not yet determined the cause of the fire or reported any injuries.