Two Harvard students were assaulted in the Cambridge Common in separate incidents last week, Harvard police said.

On Saturday night, an unidentified student suffered a laceration on his right hand when he was allegedly assaulted around 6:30 p.m. by Michael Innis, 17, of Waliham.

After the student gave police a description, two detectives searched the area around the Common, according to Deputy Chief Jack W. Morse. The detectives spotted Innis being "shoved off" one of the MBTA buses that stop at the Common, Morse said. After a witness identified Innis as the assailant, he was arrested and taken to the Cambridge Police Department for booking.

The victim was treated for his laceration at University Health Services (UHS), Morse said.

The Common was the site of another attack three days later, when two teenagers assaulted another unidentified student Tuesday night, police said. The victim described the assailants as one white male, about 17 years of age, 5'7", with a muscular build, light hair and a dark jacket; and another white male, also about 17 years old, with dark hair.

Police could not supply any further information on the incident.

Police also said they arrested a Belmont man after he allegedly robbed a Harvard student at knife poi any ate Friday night outside UHS. The victim said he was on the ramp outside the building when Jeffrey Tholand, 18, allegedly approached him with a knife and said, "Up against the wall and give me that," referring to the student's wallet.

After the victim gave police a description of the suspect, they spotted Tholand crossing Dunster Street near Holyoke Center, Morse said When the officer was 10 feet away. Tholand dropped the knife, Morse said. Tholand was taken to the Cambridge Police and booked for armed robbery.

On Sunday morning two separate, but possibly related, larcenies were reported after students happened upon the intruders in their dormitory rooms, police reported.

Between midnight and 1 a.m. a student in Claverly Hall walked from the bathroom to a bedroom in her unlocked stifle and found a Black male taking her watch and about $15 in cash. She described the suspect as about 20 years old, with a medium build and wearing a black leather jacket, police said. The victim screamed, and the suspect fled, dropping the watch. A police search of the area turned up nothing.

Also, sometime between 11:30 p.m. Saturday and 1:15 a.m. Sunday, a Grays Hall resident came back to her room and found two Black males going through her jewelery box. According to Morse, the two suspects told the victim they were looking for a party and then left taking with them $200 in jewelery.

The victim said one of the suspects was about 20 years old, 5'8", 140 lbs., had short hair, and was wearing a black leather jacket and jeans; she said the other was about 5'10", had a medium build, and was wearing a suede tan coat with a fur collar.

Morse said that there was a "strong likelihood" that the cases were related, but that so far, police had found no suspects.