Unlikely law enforcement bedfellows joined forces Monday evening to nab two armed robbers fleeing the scene of an East Side pharmacy holdup in a stolen taxi, authorities said Tuesday.

Police officers from the Port Authority of New York and New Jersey, in Buffalo for a training program, assisted local police in a Hollywood-style car chase through downtown Buffalo that culminated in the suspected robbers’ arrest, officials from the Port Authority said Tuesday.

Sisters Crystal Clark, 22, and Heather Brown, 24, of Buffalo, were arrested in the pharmacy robbery and subsequent chase. They were charged with robbery, criminal possession of stolen property and fleeing an officer, among “a host of other charges,” Buffalo police spokesman Michael J. DeGeorge said Tuesday.

According to police reports, Clark and Brown entered a pharmacy on the 2000 block of Clinton Street near the West Seneca border at around 5:30 p.m. Monday, brandishing a 12-gauge shotgun in an attempt to steal narcotics. Police said Tuesday that the sisters staged a hostage situation inside the pharmacy before fleeing in a stolen taxi.

The alleged robbers entered the Niagara Thruway and were headed to downtown Buffalo, which is where the Port Authority officers’ role began.

Three officers in a marked Port Authority vehicle saw that a Buffalo police officer had pulled a vehicle over by the Church Street exit ramp, Pentangelo said. The Port Authority officers identified themselves to the Buffalo police officer and offered their assistance.

The pulled-over vehicle was the alleged robbers’ getaway van.

The Port Authority officers’ arrival prompted Clark and Brown to flee, Pentangelo said, citing the Port Authority Police Department’s official record. The sisters drove over a sidewalk and sped through a parking lot.

The alleged robbers sped east through downtown and the East Side, according to Buffalo police. The chase ended after about five miles when the van crashed into a house on the 100 block of Jefferson Avenue at South Division Street, authorities said.

DeGeorge said West Seneca and Niagara Frontier Transportation Authority police assisted in the chase. According to police, a West Seneca police car was damaged in the pursuit.

The six Port Authority police officers were here for a course on “criminal identification and drug interdiction for motor vehicles” given by the Department of Homeland Security, Pentangelo said.