PHILADELPHIA (CBS) – Philadelphia police are searching for a suspect who has threatened pharmacy workers with a knife numerous times when they confronted him for trying to steal merchandise.

The suspect has struck four times since October of last year.

According to investigators, the suspect has targeted the Rite Aid stores located on Rising Sun Avenue and W. Wyoming Avenue.

Authorities say the suspect enters the store and removes various items from the shelves and attempts to leave the store without paying.

Each time, a store employee has attempted to stop the suspect, at which time the male produces a knife and threaten to stab the employees. The offender then runs out of the store.

The suspect is described as a light-complected Hispanic male, 30-40 years of age, approximately 5’5″-5’7″ with a medium build. He has a shaved head, with bushy eyebrows and a light mustache.

The Rite Aid Corporation, in conjunction with the Citizens Crime Commission, is offering a $1,500 reward for any information that would lead to the arrest and conviction of the suspect.

Anyone with information is urged to call the Crime Commission Tipline at 215-546-TIPS.