A police officer wounded on a subway platform in the Bronx on Friday was shot by one of her fellow officers, police officials said yesterday.

A ballistics report performed by the police department found that Police Officer Annemarie Marchiondo, who was shot three times during a struggle that took place after she attempted to frisk an armed suspect, Juan Calves, was hit at least once by friendly fire, police said.

Calves had pulled out a gun and placed Mrs. Marchiondo in a headlock. Mrs. Marchiondo was able to break free from Calves and a gunfight broke out, police said. Calves and two other suspects had been stopped by Mrs. Marchiondo and two other officers after crossing illegally between two subway cars, police said. Calves was shot and killed during the incident.

Mrs. Marchiondo was shot three times, sustaining bullets to her ankle, foot, and side, police said. The ballistics report found that a bullet, which was lodged in Mrs. Marchiondo’s left foot, was shot from a Smith &Wesson nine-millimeter pistol that belonged to a 28-year-old officer, who police did not identify.

The officer who shot Mrs. Marchiondo will not face disciplinary action because the gunfight broke out in close quarters where everyone involved was separated by a matter of feet, the head spokesman for the department, Deputy Commissioner Paul Browne, said.