BUCKS COUNTY, Pa. (CBS) – Police in three Bucks County communities are hoping to catch an armed serial bandit before he strikes again.

Police say the thief strikes just before closing time. Since October 25^th, there have been four knife-point robberies at pharmacies in Bensalem, Warminster and Lower Southampton.

In each robbery, the suspect has been described as a white male, five-nine to six feet tall wearing a face mask and dark hooded sweatshirt. He displayed an eight to ten inch Bowie-style knife and was carrying a green bag.

Bensalem Public Safety Director Fred Harran says say he uses the bag to haul off the stolen prescription medications, “You know, drugs have a big street value and whether he is using these for his own habit…but probably the amounts that he’s getting he’s probably reselling it making the money on it.”

Harran says the suspect has been caught on surveillance. “If he’s going to continue to do business in Lower Bucks County, this guy’s going to be arrested before the real meat of the holiday season gets in here. We’ll have him in custody, there’s no doubt in my mind.”

Police say he may be fleeing the pharmacies in a silver-colored sport utility vehicle. So far, no injuries have been reported.

Reported by Suburban Bureau Chief Brad Segall, KYW Newsradio 1060