CHICAGO (CBS) — Mayor Rahm Emanuel got a shaky reception Wednesday morning at a place not generally known for outbursts of protest.

The mayor was visiting Urban Prep Charter Academy in Englewood, where students wear distinctive red ties and white shirts every day to school. Emanuel was announcing a the cabinet for the local My Brother’s Keeper campaign, an effort to mentor and inspire young men of color.

There was a mixed response from students when the mayor was introduced. Some ignored Emanuel as they openly talked with each other.

Near the end of the event, when students were told to stand up to recite the Urban Prep creed, several students began chanting “16 shots,” a common slogan among protesters who want the mayor to resign over the fatal police shooting of 17-year-old Laquan McDonald. The chant is a reference to the number of bullets fired into McDonald by Officer Jason Van Dyke, who has been charged with murder in McDonald’s death.

The mayor abruptly left after the assembly, and some students resumed the chanting as they were being dismissed.

Emanuel responded in a statement released by the mayor’s office later Wednesday morning:

“The Mayor recognizes that Chicagoans are understandably frustrated. He has called for systemic reform to bring safety to every community and rebuild trust where it has been lost. As part of that process he will continue to engage with residents, police, and community leaders to address their specific concerns.”

Early Wednesday afternoon as the mayor signed a pact with major universities pledging to invest in Chicago, CBS 2 Chief Correspondent Jay Levine asked him about what happened at Urban Prep and what it said about his future.

“I can understand and appreciate people’s frustration has come to a point and I believe that we will deal with it,” Emanuel said. “I think it’s core to what he have to do, and I am committed to make sure that I use all my energy to not allow this issue to kind of be packaged with some set of reforms so we as a city can move on. That’s not possible.”