Winthrop House residents living in Gore Hall were awakened early yesterday morning because of a fire alarm set off by a burning mail basket outside room F-45.

Evacuated residents stood outside for about 30 to 45 minutes before being allowed to re-enter the dormitory. Police investigators are still searching for a cause.

The Harvard University Police Department (HUPD) received a call reporting the fire at 2:46 a.m., according to the police blotter.

When the police arrived, "officers discovered a working fire in the building," according to the blotter, which stated that arson investigators probed the fire's suspicious nature."

HUPD spokesperson Peggy A. McNamara had no additional comment when contacted yesterday.

The residents of the suite are Rachel H. Sommovilla '99 and Claire G. Schwab '99. Both students were in the room when the fire broke out, according to Sommovilla.

Schwab said they were alerted to the fire by the fire alarm, "but the situation is really a little more complicated than that," she added.

She did not say whether she reported the fire to the fire department.

"We were really freaked out," she said. The two went into Winthrop's courtyard and then to a friend's room, Schwab said. She said that she left the door unlocked.

"It's a bad subject altogether until we figure out what happened," Schwab said.

Both residents said they do not know how the fire started.

Several students offered differing accounts of the incident.

According to several F-entry residents who asked to remain anonymous, the firefighters and House staff did not have access to Winthrop House's master keys, located in the superintendent's office, for a while after the fire alarm sounded.

They were unable to enter F-45, the students said, and did not know where its occupants were.

Occupants of the neighboring room, F-44, said the fire alarm did not fully rouse them from sleep.