A group of teenagers is responsible for 13 armed robberies across Chicago within a span of five hours, police said Monday. 

The Chicago Police Department said the teens exited a vehicle and approached victims on foot while displaying firearms. The victims were robbed and the suspects fled to an awaiting vehicle, police said. 

CHICAGO WOMAN WITH CONCEALED-CARRY LICENSE FOILS ATTEMPTED CARJACKING BY SHOOTING MAN IN HEAD

The incidents occurred between 2 a.m. and 7 a.m. Monday. The suspects were described as four Black males in their late teens. 

They were armed with semiautomatic weapons that were black and silver and black, authorities said. They were wearing dark clothing and their faces were covered with "surgical-type masks," police said.

The robberies came following a violent weekend in Chicago.

There were 24 reported shooting incidents and 31 shooting victims, which included at least four juveniles. Police said at least six people were murdered in the weekend violence.