Chicago police are searching for a crew that committed 10 armed robberies in just 30 minutes Sunday morning.

The rapid string of robberies occurred between 7:20 a.m. and 7:50 a.m. Sunday in the Hermosa and Humboldt Park neighborhoods, police said.

The four attackers drove a gray Hyundai Elantra and wore black hooded sweatshirts and black ski masks. They approached victims on the sidewalk or while parking their car, then demanded victims’ property while brandishing semi-automatic handguns, police said.

Police warned people in the area to be vigilant in a news release Sunday afternoon and encouraged anyone with information about the attackers or their car to contact the police department’s detectives bureau at 312-746-7394.

Below are the time and locations police reported for each attack:

• 3900 Block of West North Avenue at 7:20 a.m.

• 3900 Block of West Le Moyne Street at 7:30 a.m.

• 1800 Block of North Kedvale Avenue at 7:32 a.m.

• 4100 Block of West Wabansia Avenue at 7:34 a.m.

• 4400 Block of West Palmer Street at 7:35 a.m.

• 4400 Block of West Palmer Street at 7:37 a.m.

• 4300 Block of West Dickens Avenue at 7:38 a.m.

• 2200 Block of North Kenneth Avenue at 7:40 a.m.

• 1700 Block of North Pulaski Road at 7:41 a.m.

• 4100 Block of West Palmer Street at 7:50 a.m.