The shooting happened around 6 p.m. at Eastland Mall, east of Detroit, on the heels of Black Friday, traditionally the kickoff for what retailers hope is the busiest weekend of the holiday season. The mall was closed for the night as police searched for suspects, said Harper Woods deputy police chief Jim Burke.
The 18-year-old victim, a member of the rival group, was struck in the chest, and a stray bullet hit the leg of the worker, in his mid-30s, who was standing outside the clothing store, Burke said.
"He just happened to be standing out there and this broke loose," Burke said.
Both were taken to St. Johns Hospital in Detroit. Burke said they were listed in critical condition but were expected to survive. A hospital spokesman declined to confirm this or release any information, citing privacy laws.
Burke said that the shooting caused panicked shoppers to run for cover or exits as chaos unfolded inside the mall, which has more than 100 stores and restaurants according to its website. He said between 20 and 30 shoppers called 911 to report the shooting.
Standing outside the mall about two hours later, 15-year-old Tatianna Renfroe said she had been in a hair salon with relatives a floor below the shooting site.
"We heard shots. People were stomping, running and screaming," she said, adding that in the salon "everybody hit the floor."
After the shooting, Renfroe said she and her relatives remained inside the salon for 20 minutes, behind the doors locked by the salon manager.
Burke said officers were still looking for the two teens involved nearly three hours after the shooting. He said the two rival groups had been involved in some type of dispute that had gone on for weeks.
This was at least the second shooting in three months at the mall. In September, a man sitting in his car in the mall's parking lot was shot to death by a suspect who fired four shots and then fled with another man in a car.