Police are investigating a string of armed robberies reported Sunday on the North and Northwest sides.

In each incident, three to six men wearing dark colored clothing and black ski masks jumped out of a stolen car then would brandish multiple firearms, including rifles, before robbing their victims and fleeing, according to Chicago police.

For most victims, the robbers also demanded they share their phone passwords, police said.

The incidents were reported between 4 a.m. and 6 a.m.

According to police, the eight robberies occurred:

• About 4:20 a.m. in the 700 block of North Milwaukee Avenue
• About 5 a.m. 2100 block of West Farwell Avenue
• About 5:10 a.m. 7000 block of North Ridge Boulevard
• About 5:10 a.m. 5000 block of North Northwest Highway
• About 5:40 a.m. 3500 block of West Lawrence Avenue
• About 5:50 a.m. 5100 block of North Elston Avenue
• About 5:50 a.m. 5100 block of West Foster Avenue
• About 6 a.m. 4100 block of North Cicero Avenue

Anyone with information is asked to contact Area Three Detectives at (312) 744-8263.