A disgruntled tenant shot dead his building manager and wounded four other people in an upscale neighbourhood of Washington on Thursday before killing himself, police said.

The shooting, which occurred about a mile north of the White House, sparked a massive police response in the nation's capital with dozens of law enforcement vehicles racing to the scene and police helicopters hovering overhead.

Jeffery Carroll, Washington's interim police chief, told reporters that the gunman, identified as Matt Lambert, 55, had been involved in an ongoing dispute over maintenance with the condominium association for the building where he owned an apartment.

Lambert, an emergency medicine physician, fatally shot the building manager in a gym attached to the complex, located in the Logan Circle neighbourhood, and then barricaded himself in his seventh-floor unit, Carroll said.

He then opened fire from his balcony on people below, wounding four. One of the wounded was in critical condition while the others did not have life-threatening injuries.

Lambert fired at least twice at police through his apartment door before shooting himself, Carroll said. He was pronounced dead at the scene.

Carroll said Lambert had taken legal action against the homeowners association of the condominium complex where he lived over what he considered to be a lack of maintenance of the building.

An X feed reportedly linked to Lambert titled @OfMiceandMold is a litany of complaints about mould and water damage. The final post, described as a "manifesto," is an engineering report detailing problems with his apartment.

Washington Mayor Muriel Bowser denounced what she described as a "senseless act of gun violence."

The shooting occurred during the busy morning rush hour, snarling traffic as police closed off streets around the area and evacuated residents.

The Washington Sun quoted a member of the VIDA Fitness gym as saying that he was on a treadmill at the workout facility when the shooting began.

Michael Carney said he heard a "pop" and then saw someone on the gym floor who had been shot in the head.

"Everyone was kind of just hiding behind planters and stuff," Carney told The Sun.

The Logan Circle neighbourhood is one of the most expensive in Washington and is known for chic restaurants and nightlife spots. It also sits a short distance from a heavy concentration of foreign embassies. (AFP)



Edited by Cecil Wong