A massive wave of violence ripped through the city of Chicago this weekend, with several residents shot, many fatally, in a matter of hours.

The Chicago Tribune reports that starting around midnight Saturday, at least 40 people were shot citywide in less than seven hours. That number has since increased to at least 57, according to a CBS News update. So far, eleven gunshot victims have died from their injuries. Police say the gunmen targeted groups at a block party, one after a funeral, another on a front porch, and several other gatherings around the city.

Chicago’s West Side was hit heaviest, as 25 people were shot in separate attacks between midnight and 6:50 a.m. Sunday. The South Side saw the single largest attack, with eight people sustaining injuries in a Gresham neighborhood shooting, including a 14-year-old girl.

Chicago police chief of patrol, Fred Waller, called out gang members during a Sunday news conference, believing they take advantage of large crowds to seek revenge on their adversaries.

“I promise this city, we won’t be defeated,” Waller said. “We won’t be overrun by that small element that’s committing these reckless acts.”