Around 4:45 a.m. Sunday, the 6201 Ridge Avenue, was robbed, Sgt. Michael Wierchinski said.
A man walked into the store, pointed a silver handgun at the employee's back and demanded money, Wierchinski said, adding that the man got about $250.
He fled north on Ridge Avenue on foot. The employee was unharmed.
As of about 6:15 a.m. Wierchinski said detectives were reviewing surveillance video, no suspects were taken into custody yet.