Two alleged robbers were shot while officers attempted to apprehend them in Brooklyn and Queens last night, police said.

At around 8:26 p.m. in Bedford Park in the Bronx, two officers were told by a passer-by that a gunpoint robbery had just happened at a gas station at Bedford Park Boulevard and Grand Concourse. The officers pursued the suspect, who was also being chased by the victim of the robbery.

According to police, during the pursuit, the robber turned toward officers while holding a gun. The officers opened fire, hitting the robber once. He was taken to Saint Barnabas hospital, and is listed in critical but stable condition.

Recovered from the scene was his gun, which was a black imitation pistol with a wood-grain stock.

At around 9:03 p.m. in Fort Greene, Brooklyn, two plainclothes officers saw a 29-year-old woman chasing after a man after an apparent robbery. According to police, while trying to apprehend the alleged robber, one round was fired, grazing the man in his left shoulder. He was then arrested, and charged with grand larceny.

The suspect was taken to King’s County Hospital and is listed in stable condition.

Also last night, two Queens roommates were arrested for stabbing another man to death on Halloween in a barroom fight over a woman, police said. Sergio Carrillo, 19, of Union Street, was arrested at 1:30 a.m., and his roommate Regino Dominguez, 23, was arrested three hours later, police said.

Mr. Carrillo and Mr. Dominguez are accused of stabbing Patricio Guaman, 22,of 94th Street, at 1:48 a.m. Sunday in an Elmhurst bar at 95-27 40th Road, police said. Guaman was stabbed in the head, arm, and body and taken to Booth Memorial Hospital, where he was pronounced dead three hours later, said police.

A relative of the homicide victim, Franklin Guaman, 23, and Marco Chaboo, 21, suffered stab wounds to the chest and were taken to Booth Memorial and Elmhurst Hospitals, respectively, police said.