AUBURN — A Portland man was being held Sunday night on $50,000 cash bond after being tracked down by a K-9 unit following an armed robbery Saturday night on Hampshire Street — less than 30 hours after being released from jail after his arrest on a warrant charging him with theft.

Deputy Chief Jason Moen of the Auburn Police Department reported Sunday that officers arrested Christopher Libbey, 24, in the basement apartment of a building on Gamage Street. The arrest came shortly before 9 p.m. Saturday after units responded to reports of an armed robbery at Gowell’s Market at 121 Hampshire St.

According to the report, the armed robbery occurred about 8:51 p.m. when a suspect wearing dark pants, a black hooded sweatshirt with a white T-shirt over it and a dark mask entered the store, brandished a large knife and demanded money. The male then fled the store on foot with an undisclosed amount of cash.

Moen reported that Cpl. Scott Corey and his dog Inka tracked the suspect to the basement apartment, where officers found several people. Officers developed evidence leading to Libbey’s arrest through interviews and a search of the apartment. Libbey is a transient whose last known address was 71 Chesley St. in Portland.

Officials at the Androscoggin County Jail confirmed Sunday that Libbey was arrested by Auburn police Thursday night on a warrant charging him with theft by unauthorized transfer and possession of scheduled drugs. The latter charge of the warrant was dropped, and Libbey was released at 4:02 p.m. Friday. The officer at the jail said Libbey’s release could have been because he appeared in court Friday and was sentenced to time served.

Calls to the Auburn Police Department on Sunday to clarify Libbey’s arrest and release were not immediately returned.

Moen reported that detectives believe the Saturday night robbery at Gowell’s and an earlier armed robbery at Dave’s Other Place in Auburn are related. In that incident, Auburn police responded shortly before 11 a.m. Saturday to Dave’s Other Place, a variety store at 539 Washington St.

According to that report, a suspect wearing blue jeans, a white hooded sweatshirt and a sheet covering his face entered the store, brandished a large knife and fled on foot with an undisclosed amount of cash and cigarettes

Libbey could face an additional robbery charge following the investigation, according to Moen.