Gunman kills one, wounds four in busy Washington, DC, neighborhood

A gunman killed one person and wounded four others in a busy Washington, DC, neighborhood ‌on Thursday before barricading himself in his apartment and eventually taking his own life following a standoff, officials said. The suspect, whom police identified as Matt Lambert, 55, had been embroiled in a longstanding dispute with his condominium association over mold and moisture in his apartment.

"We believe it's related to that," Metropolitan Police Interim ‌Chief JW Carroll told a press conference on Thursday afternoon. Police identified the dead man as James Stuart, 46, the manager of the building, and ‌said he appeared to have been deliberately targeted.

The attack began just before 8 a.m. EST (1300 GMT) inside the gym, where police said Lambert shot and killed Stuart with a handgun before returning to his seventh-floor apartment. He then opened fire from his balcony with a rifle, striking four people, Carroll said. Lambert also fired through his door at officers in the hallway and ⁠set a ​fire, according to Carroll. Police negotiators were ⁠able to speak with Lambert on the phone, but when they heard a gunshot, they forced their way into the apartment and found him dead from a self-inflicted gunshot wound. ⁠Officers found three guns as well as gasoline inside the apartment.

One of the four wounded people was in critical condition, and the other three suffered non-life-threatening injuries. SNIPERS ON ​ROOFTOPS

The standoff brought the normally bustling neighborhood to a standstill, as large numbers of officers in tactical gear and dozens of emergency vehicles ⁠flooded the area, shutting down streets and stationing police with rifles on rooftops. One person who said he witnessed the incident told Reuters he heard gunshots and saw one man run to ⁠another ​who appeared to have been struck by a bullet.

"Blood was pouring immediately, and he said, 'He's dead,'" the witness said. "We didn't know if the gunman was still on the premises, so we just ran frantically." Lambert, a doctor, first sued the building's condo association in 2025 over what he described as ⁠intrusive water and mold that rendered his unit unlivable. In court papers, Lambert said he had spent approximately $300,000 on remedial work.

The condo association denied the ⁠claims and filed its own countersuit against ⁠the gym that occupies the building's first floor, alleging that the facility's commercial dryers were the likely culprit. The dispute was still pending at the time of the shooting.