CHICAGO (CBS) — Three University of Chicago students were robbed within a period of half an hour overnight, and one holdup happened right in the Main Quadrangle.

The first robbery happened around 11:35 p.m. as two students walked down 57th Street at Dorchester Avenue. The suspect stuck up the two students at gunpoint and took their cell phones, then fled north on Dorchester.

The area where the first robbery occurred is a quiet and leafy residential district several blocks east of campus, and a short distance from a busy block that includes the campus hangouts the Medici restaurant and Noodles Etc. on Campus.

The second robbery occurred at 12:05 a.m. right in the U of C Main Quadrangle. The quad is bounded by 57th Street on the north and 59th Street on the south, University Avenue on the east and Ellis Avenue on the west.

Three men approached a student and took out a gun, and robber the student of a cell phone and book bag before fleeing west to Ellis Avenue.

A campus security alert did not specify exactly where on the main quad the robbery occurred.

U of C students are known to cross the main quads at all hours of the night, but robberies are not common.

Investigators will review surveillance video for evidence in the robbery on the quad.

While these two incidents were the only ones that made a campus security alert issued Monday, there was another robbery in Hyde Park earlier Sunday evening.

Around 8:35 p.m., a man was robbed at gunpoint in an alley off 52nd Street between Kimbark and Kenwood avenues. A U of C Police daily incident report did not specify further details, or whether the victim in that case was a student.

In the wake of the latest robberies, U of C police advise students to be alert, and report suspicious activity immediately using an emergency phone on campus. Anyone with information on these robberies should call 911, or U of C police at (773) 702-8181.

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