WASHINGTON – A transit employee was killed and three others were injured on Wednesday morning after a gunman confronted people on a bus and later in a metro station in south-east Washington in the US, the police said.

Officials said the employee was trying to protect a customer when he was killed.

Bystanders later tackled the gunman, the police said, and he was taken into custody at the station.

According to the police, the violent string of events began shortly after 9am with an altercation on a Metro bus, where the attacker brandished a weapon and then followed a passenger off the bus and shot him in the legs.

The gunman then went down the escalator into the Potomac Avenue Metro station and came upon a person buying a fare card, and proceeded to shoot the person in the leg after another altercation. The attacker then made his way to the platform and confronted a woman.

Mr Ashan Benedict, the executive assistant chief of the Metropolitan Police Department, said at a news conference that a transit employee tried “to intervene to protect this young lady”.

“By doing so, he’s immediately shot by our shooter,” he said.

The employee was later identified as Mr Robert Cunningham, 64, a mechanic in Metro’s power department.

Mr Benedict said: “His heroism has to be recognised here today.”

A second transit worker was apparently able to de-escalate the situation, the police said. The gunman at one point got on a train at the station but then got off, and he was tackled by bystanders before being taken into custody.

In addition to Mr Cunningham and the two people shot in the legs, another person sustained a hand injury.

Mayor Muriel Bowser said: “We don’t know a lot about this shooter at this moment, other than we had a person with a gun who’s created yet another tragedy in our city.”

Crime on public transit has posed a problem for leaders in cities around the country amid the Covid-19 pandemic, with high-profile incidents threatening to deter commuters from returning to the trains, buses and subways they relied on before the coronavirus disrupted routines.

“This is not a Metro-specific safety issue,” said Mr Randy Clarke, the general manager of the Washington Metropolitan Area Transit Authority, or Metro. “It’s an American gun violence issue, and I think that’s becoming increasingly clear all over America.” NYTIMES