Chicago police hope security video from a North Side convenience store will help them find the two people who exchanged gunfire with the store clerk early Friday morning.

An employee of the 7-Eleven store, on the 2900 block of West Montrose Avenue, said he and his boss were working at the store when two masked men walked in at about 1:30 a.m. At least one of the robbers had a gun and demanded cash.

One of the robbers pointed a gun at the employees and demanded money. After the store owner handed over the cash, he followed the robbers out of the store, according to the other employee. The clerk then heard the robber say, "Stop following me," and gunshots ensued.

Nobody was hurt, and the robbers got away in a car.

Charmaine Hobbs, who lives near the 7-Eleven, heard the gunfire and called 911.

"I was listening to the radio, and I turned it off, and minutes later, I heard someone say, 'Stop following me,'" Hobbs said. "And then the other guy said, 'I'm tired of you.' Then the shots rang out."

The area was clear of detectives by 5:30 a.m.

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