Security remained high Monday around Harvard University, where two women were raped within a week, as police asked for the public’s help in solving the crimes.

“We’re asking anyone who may have information to please come forward,” said Dan Riviello, a Cambridge ­Police Department spokesman.

Police have deployed additional units to Harvard Square since the second rape was ­reported Friday, and have told officers to give extra attention to the campus, he said.

Riviello declined to comment on the status on the inves­tigation. There have been no arrests.

On Aug. 10, a woman ­reported she was raped in Harvard Yard about 3:15 a.m. She was grabbed as she ­entered the yard, pulled behind a building, and attacked, police said.

‘If you are out after dark, try to travel in groups, use only well-lit routes or designated pathways, and do not allow yourself to be distracted by phone calls or by using ear buds.’

She described her assailant as a “very tanned” man in his mid-20s with a medium build and dark hair.

Four days later, on Aug. 14, a woman was raped sometime after 11 p.m. near the university’s science center, police said. She described the offender as a white male in his mid-20s with a thin build and dark, spiky hair.

Authorities believe the rapes are unrelated.

The second victim reported the incident Friday, prompting Harvard police to increase uniformed and plain-clothes officers around campus and warn students to take precautions.

“If you are out after dark, try to travel in groups, use only well-lit routes or designated pathways, and do not allow yourself to be distracted by phone calls or by using ear buds,” read the advisory. “If you suspect you are being followed, stay away from dimly lit areas and head for a store or building that you know to be open.”

A spokesman for the ­Harvard Police Department could not be reached for comment.

Anyone with information can contact Cambridge police at 617-349-3370, or visit www.CambridgePolice.org/Tips to provide information anonymously.