Officials in the US city of Virginia Beach have named the 12 people killed by a gunman who went on a rampage in a municipal building on Friday.

City manager Dave Hansen said the victims - 11 local authority workers and one contractor - "leave a void we will never be able to fill".

The gunman shot indiscriminately before dying in a gun battle with police.

He has been identified as DeWayne Craddock and described by police as a disgruntled city employee.

Authorities said they would only refer to him by name once, in order to focus attention on the victims.

What is known about the victims?

The municipal workers killed were Laquita Brown; Tara Gallagher; Mary Louise Gayle; Alexander Gusev; Katherine Nixon; Richard Nettleton; Christopher Kelly Rapp; Ryan Keith Cox; Joshua Hardy; Michelle Langer and Robert Williams.

Robert Williams had worked for the authority for 41 years, the news conference was told, while Christopher Rapp had been there for only 11 months.

The contractor was identified as Herbert Snelling.

"Today we all grieve," Mr Hansen said.

At least four people are known to have been wounded, including a police officer whose life was saved by his bulletproof vest.

What about the gunman?

Police said DeWayne Craddock, 40, had been employed as an engineer with the city's public utilities department for 15 years.

According to AP news agency he had served in the military and was described by neighbours as quiet and "rarely smiling".

Virginia Beach Police Chief James Cervera declined to comment on a motive for the shooting. He said the gunman had been armed with a .45-calibre semi-automatic pistol equipped with a sound suppressor and high-capacity magazines.

CNN says DeWayne Craddock is listed on department press releases as a point of contact for information on local road projects.

How did the shooting unfold?

The attack began shortly after 16:00 (20:00 GMT), at Virginia Beach Municipal Center. The area was put into lockdown by police and employees were evacuated.

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One of the victims was shot outside in a car and the rest were found over three floors of the government building.

Four officers entered the building, located the gunman and engaged him, police said. The attacker was then shot dead.

According to US tracking website Gun Violence Archive, the incident is the 150th mass shooting in the US so far in 2019.

The site defines a mass shooting as a gun attack in which at least four people are either killed or wounded. (BBC)

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