"We hope the investigation will determine whether they were acting in concert," she said.
McNamara urged students to be aware of their surroundings, to try to walk in groups and to report any suspicious activity immediately.
The number of street robberies increased three-fold over the past year in the neighborhood encompassing Leverett House, according to statistics released yesterday by the Cambridge Police Department.
The area around Leverett House was the subject of several incidents last year, including an indecent assault last September at the same location. Earlier in the year, a pack of robbers moved through the area in a one-night crime spree that included four robberies and two assaults. No one was arrested in any of the incidents.
Anyone with information about the robbery is requested to contact HUPD's Criminal Investigation Division at 496-1796.