The HUPD Criminal Investigation Unit is working with a case investigator from CPD on the matter.
A police investigation of this kind involves basic detective work, said CPD's Sullivan.
"We'll bring the victims in to view photos and see if they can identify perpetrators, examine to see if there's any physical evidence at the scene, interview any witnesses that may have observed anything," Sullivan said.
Sullivan said the investigation will take between a few days and several weeks, depending on the kind of evidence that is found.
Last week's incident is the third reported armed robbery on campus this year. Two others took place on the evening of February 22 when a group of four teenagers went on an evening crime spree, robbing two undergraduates at gunpoint before committing two more robberies in Cambridge.
The suspects were never caught and the case was closed without a finding.
McNamara said that though there is no reason to think the June 6 incident is related to the previous two robberies, investigators are examining all leads.