An off-duty D.C. police officer fired gunshots Saturday in Northwest Washington after encountering two men who appeared to be armed and firing, a police spokeswoman said.

It was not clear whether the officer’s shots hit anyone, according to Aquita Brown, the spokeswoman.

However, Brown said, two men arrived at a hospital with wounds that authorities thought might have resulted from gunfire.

Police were investigating to determine how the men had been wounded and whether either had been hit by the officer’s gunfire.

Although details of the incident remained unclear late Saturday, authorities said it occurred about 8 p.m. at Georgia Avenue and Ingraham Street NW

It had not yet been determined whether the two men encountered there by the officer were firing at each other or at another target, Brown said.

Both of the men at the hospital were described late Saturday as conscious and breathing.

The officer was not identified, and the officer’s gender could not be learned.

The incident is under investigation by the police internal affairs unit, Brown said. Such investigations are routine when police fire weapons.

A woman who lives near the scene of the shooting said she thought she heard about six shots.

First, she said, came a burst of about four shots, followed by two shots.

She thought nothing of it, she said, suspecting that the sound was that of firecrackers.

But then, she said, she heard the sirens of arriving police cars.

The site of the gunfire is about a half-mile east of Rock Creek Park and its tennis center. It lies between the neighborhoods of Brightwood Park and 16th Street Heights. Georgia Avenue is lined with stores and businesses in that area, but there are houses on the intersecting streets.