The heist occurred at a Cellular Connection outlet in the 20000 block of West 10 Mile Road near Evergreen.
Police say the suspect spent time looking through the windows, apparently casing the place, waiting for it to be empty of customers.
The man entered the store at 9:05 a.m., when only a female sales clerk was inside.
Brandishing a silver-colored, semi-automatic pistol, the thief first demanded an undisclosed amount of cash in the till. The employee complied.
Then the suspect asked for iPhones. The employee opened a safe in a backroom that contained six of the phones, and she surrendered these.
The thief then bound the clerk’s hands behind her back with zip ties. She eventually struggled out of them and contacted her manager, who called the police.
By then, the suspect was gone.
The thief is described as a black male with a dark complexion, in his late 20s or early 30s, 5’5”-5’7” tall with a medium build.
Anyone with information about the theft is urged to call the Southfield police at (248) 796-5500.