Fire ripped through a Washington Heights apartment building early yesterday, injuring seven people, officials said.

The blaze broke out on the fifth floor of the building on Riverside Drive and West 160th Street at 1:30 a.m., authorities said.

The flames raged for nearly two hours before firefighters got them under control.

The seven people, none firefighters, were treated for minor injuries at New York Presbyterian Hospital, a Fire Department spokesman said.

The cause of the fire is under investigation.