Two men tried to rob a Winthrop House resident in the House's junior common room (JCR) Monday night, turning off the lounge's lights and demanding money from the student.

The male resident was alone in the common room around 8 p.m.

Police say the two suspects knocked on a door to the room. When the student asked the men if they were students, the men entered the room and turned the lights off.

They then told the student to give them any money he had.

At that point, the door to the room "swung open" and the men ran out, according to a HUPD community advisory.

They did not escape with any cash.

HUPD spokesperson Peggy A. McNamara refused to divulge any additional details about the incident, citing an on-going investigation.

The community advisory describes the suspects as black males between 18 and 20 years old.

One suspect is six feet tall and has a mustache. He wore a red and blue woolen hat, blue jeans and a dark blue ski parka.

The other suspect is around five feet, 11 inches tall and wore dark clothing and jeans.

McNamara and several Winthrop House staff members said they did not know how the men were able to enter Winthrop House or the common room, which is accessible from the main hallway in Gore Hall and through a door leading to the Winthrop House courtyard.

"They could have piggy-backed in behind someone or someone could have inadvertently thought they look like students," McNamara said.

The junior common room is protected by a card key lock and can also be manually locked.

An HUPD security guard was on-duty the evening of the robbery attempt, Winthrop House residents and staff said.

The guard's office is in G-entryway, several doors away from the junior common room.

The security guard on duty last night said guards routinely patrol house grounds in the evening.

Winthrop House Master Paul D. Hanson said that the usual night watch- man, George Perry, is "remarkably responsive, awonderful person," and that he did not fault himin the least for the incident.

Jennifer M. German '00, a Winthrop Houseresident, said students regularly let in anyonewho knocks on the large door to Winthrop House onMill Street.

The JCR is located just off the hall to whichthe Mill Street door bars access.

Last night, House residents let in severalstudents without inquiring about their identity.

"We're not usually careful about that aroundhere," German said.

"[Students] don't usually check for ID. Iusually don't," she said. "I should!"

As of 5 p.m. yesterday, most House residentssaid they did not know about the robbery attempt.

They said they had not received any e-mail orwritten notification about the incident.

Hanson said that he met with the studentyesterday, and that enhancing security has been a"top item" on the Winthrop House agenda in thedays since the incident.

Hanson and Senior Tutor Sarolta Takacs saidthey had been in discussion with HUPD andAssociate Director for Building Services Robert L.Mortimer, but that it was too premature toimplement changes.

"We might know better in a week," Hanson added.

This is the third time in two weeks that aHarvard student has been the victim of a robberyor robbery attempt.

On Jan. 9, armed assailants robbed twoundergraduates at knife-point late at night at theintersection of Follen Street and Concord Avenue.

The suspects, both white males in their lateteens or early 20s, made away with a bikebelonging to one of the students.

Cambridge police and HUPD are working togetherto solve that crime.

On Jan. 13, a Mather House junior was mugged bytwo men near the intersection of Bow and Arrowstreets.

The men demanded the student's CD player andcash and threatened to hurt him with a weapon ifhe did not comply.

No one was injured in the robberies or any ofthe three incidents.

McNamara said there is no indication thateither of the two robberies and the attemptedrobbery are related.

"At this point, any connection is unknown," shesaid