CINCINNATI — Police in Cincinnati are trying to determine what happened in the moments before a fatal shot was fired by a store clerk who said he believed he was being robbed by a man wearing a motorcycle helmet.

The Cincinnati Enquirer reports ( that police don't believe Omar Magdy Abouelalla had a weapon. The 22-year-old man rode his motorcycle to the supermarket and was wearing his helmet when he went inside.

The LM&N Unlimited Supermarket clerk called 911 at 8:46 p.m. Sunday to report that he shot a man inside the store, police said. Abouelalla was dead at the scene, police said. The Hamilton County coroner said he died of a single gunshot wound to the chest, but didn't immediately release any other information.

Police interviewed the clerk and reviewed store surveillance video Monday. The 32-year-old clerk's name wasn't immediately released.

"We are not sure of the facts yet," police Lt. Michael Savard said.

The Hamilton County coroner said Monday that Aboudelalla died of a single gunshot wound to the chest.

Police said they were keeping in communication with the Hamilton County prosecutor's office as they continued their investigation into the shooting, in the Pleasant Ridge neighborhood in the city's northeast.

"We just have to get as much information as possible before making a decision," Prosecutor Joe Deters said. He said a decision on any charges in the case will probably come by the end of this week.

A black tarp covered the store's entrance Monday and a note said it was closed for the day.