PALO ALTO -- A retail clerk required stitches for a head wound following a robbery Tuesday night in Palo Alto but it is unclear exactly how he was hurt.

Palo Alto police Agent Dan Ryan said today that a man wearing a bandana over his face entered the WeFixMacs store at 3159 El Camino Real at approximately 6 p.m., closing time. The man apparently brandished a handgun, announced the robbery and started stacking up laptops, setting his gun on the counter. When the clerk reached for the gun the suspect tried to stop him and a struggle ensued. The gun went off and the clerk was injured with a cut on his head. Exactly what caused the injury, however, is not clear, Ryan said.

"It could have been grazing from the bullet, it could have been grazing from the action of the gun or he could have hit his head on the table," said Ryan.

The suspect, described as a black man, 30 to 35 years old, 5 feet 10 inches tall, 200 pounds and wearing sideburns leading into a partial beard, continued collecting equipment after the scuffle, according to police. As he was leaving the store he ran across two janitors about to enter the building for cleaning.

"He ordered them in and ordered them on the ground," said Ryan, but not before they apparently got at least a partial look at the face behind the bandana.

Police have released two sketches of the suspect, one with and one without the bandana. Anyone with information about the incident or the suspect is asked to call the police tip line at (650) 329-2190