A gang-related shootout at a kid’s birthday party in the suburbs of Chicago early Sunday left seven wounded, one critically, authorities said.

Investigators said the shooters arrived on bikes and on foot, fired multiple shots, then fled north on Grand Avenue in Aurora, Illinois, WGN reported.

“The only suspect information we were able to gather is that the shots were fired by several males dressed in dark hooded sweatshirts,” police told The Aurora Patch on Sunday. “It also appears that someone at the party returned fire.”

Police arrived at the scene shortly after midnight to find six wounded; the seventh victim had been driven to the hospital by a relative.

According to The Chicago Sun-Times, the victims were five men, ages 21, two 22-year-olds, a 25-year-old and a 28-year-old. The 21-year-old man is in critical condition. Two woman ages 27 and 30 also were shot.

On Facebook, the Aurora Police Department requested anyone with information about the shooting to call Aurora Police at 630-256-5500 or Aurora Area Crime Stoppers at 630-892-1000.