CHICAGO (CBS) — Chicago police are warning about a series of robberies in the Streeterville and Gold Coast neighborhoods this month.

Ald. Brian Hopkins (2nd) called for more police in the area, following a string of brazen robberies in an incredibly busy area just north of downtown.

The two latest robberies happened overnight. Just after midnight Monday night, a 54-year-old woman was walking to her car outside Prentice Women’s Hospital, near Superior and Fairbanks, when a robber attempted to snatch her purse. The woman struggled, and another man approached from behind and stole her phone, shoving her to the ground. The robbers fled the scene in a black SUV. The victim was not injured.

Four hours later, about a block away, a man was punched in the face while walking on Chicago Avenue near Lake Shore Park. Two robbers stole his iPad, and fled the scene in a silver sedan.

Hopkins said the robberies are alarming.

“The violence associated with them is very disturbing, and the two cases that happened last night, the victims did not resist. They were compliant, and yet they were still physically struck and physically assaulted,” he said.

The alderman said there is video evidence of the two crimes from overnight, but so far, there have been no arrests.

“We need increased patrols in this area. When these offenders are arrested, we need to take it seriously. They need to be held, they need to be subjected to the full force of the criminal justice system,” he said.

There have been a total of ten similar robberies in Streeterville and the Gold Coast this month, including three within less than half a mile of each other on March 1.

Graduate student Sarah Bond said she won’t be wearing her earbuds in public until the robbers are caught.

“Especially when I get out of class late at night,” she said. “Definitely something I’ll think twice about.”

The robberies have stretched from Oak Street on the north to Erie Street on the south.

In one of the robberies, the attackers showed a handgun and threatened to shoot the victim.

Hopkins said there’s no reason to believe all the robberies are linked, but he certainly can’t rule that out.

Mike Puccinelli