BRIDGEPORT — A fire that severely damaged the South End home of about a dozen University of Bridgeport students was under investigation Wednesday by police.

Fire Marshal Bruce Collins said he referred the case to the Police Department's arson investigators after determining the cause of the fire to be suspicious.

The fire broke out shortly before midnight Tuesday in a three-story house on Park Avenue between Gregory Street and Park Terrace.

Two students were slightly injured jumping from the second floor to escape the blaze.

University officials relocated the students to other housing.

Eleven of the students came to the Southeastern Fairfield County chapter of the American Red Cross Wednesday, where they were given a clothing allowance, said Lyn McCarthy, development director.

When firefighters arrived, heavy smoke was pouring from the building's windows.

Collins said the fire began on the front porch and spread throughout the wood-frame structure.

He said the cause of the fire was "incendiary."

The blaze was brought under control in about an hour.