ROCKLAND, Maine — A 55-year-old Owls Head man will remain at the Knox County Jail following his arrest Tuesday evening on a charge that he robbed the Kennebec Pharmacy and Home Care in Rockport while wearing a shopping bag on his head.

Donald R. Keating Jr. was arrested and charged with robbery. Bail on the robbery charge was set at $25,000 cash by Judge Susan Sparaco during Keating’s initial appearance Wednesday afternoon in Rockland District Court. But Keating remained jailed on a probation violation for which no bail was set.

Assistant Attorney General Christopher Fernald confirmed that the U.S. Attorney’s Office has been notified as is standard practice with all pharmacy robberies, since there is a potential for the case to be handled at the federal court level.

Pharmacy employees told police that they had seen a man hanging around outside the store on previous occasions, according to an affidavit filed with the court by Rockport Police Officer Cooper Plaisted. On Tuesday, Keating walked up to the door and put a Hannaford shopping bag, with two eye holes cut out, on his head, according to the officer.

Keating then walked into the store, went to the counter and demanded morphine. He told employees that they had 30 seconds to meet his demand, according to Plaisted’s report.

No weapon was displayed and none was mentioned by him, the affidavit states. Keating was given the drugs and he left the store.

Keating then fled through the pharmacy’s parking lot and through a narrow buffer of trees that led to the parking lot of the Oakland Commons medical practices. A staff member from the pharmacy followed Keating to the tree line and watched him get into a dark-colored vehicle and drive away. The employee was able to get a license plate number from the vehicle, according to Plaisted.

Police then determined that the vehicle belonged to Keating’s son and that the description of the man who robbed the store matched the elder Keating.

Pharmacy staffers also were shown a photo lineup with Keating’s photo and identified him, according to the affidavit.

Knox County deputies went to Keating’s home on the Ballyhac Road in Owls Head. Keating was not in the house, but Deputy Jeremy Joslyn and his tracking dog Gunner were able to locate him about 100 feet into the woods.

He did not resist and was arrested and taken to the jail in Rockland.

According to the affidavit, Keating confessed to the robbery. He said he dumped the morphine in a dumpster in Rockland when he saw a Rockland police cruiser parked at Pizza Hut.

Rockport Police Chief Mark Kelley credited the assistance of other departments with the quick apprehension of Keating. Detective Sgt. Chris Young and Sgt. Russell Thompson of the Rockland Police Department along with officers from the Maine Drug Enforcement Agency and the Knox County Sheriff’s Office joined with Rockport police in the investigation.

The pharmacy is located off Route 1 across from the entrance to Pen Bay Medical Center.

Keating was convicted in 2003 of 11 counts of sexually assaulting a girl from 1989 through 1992. He was sentenced to 15 years in prison with all but seven years suspended. He also was ordered to be on probation for six years upon his release.

He also was charged last year with the theft of an air conditioner from the Thomaston transfer station. He pleaded guilty in January to criminal trespass and was sentenced to seven days in jail.

Keating also is the subject of a land-use appeal by neighbors who oppose a take-out stand, the Beach Side Grill, that he opened near his home. That case is under advisement by a judge.