An employee at a Walmart supermarket in the US state of Virginia has shot dead six people and injured four others, police say.

An employee at a Walmart supermarket in the US state of Virginia has shot dead six people and injured four others, police say.

He later turned the gun on himself and died of a self-inflicted gunshot wound. The motive is still unknown. Police are not searching for anyone else in connection with the attack.

The first emergency call was made at 22:12 local time on Tuesday (03:12 GMT Wednesday) and officers arrived at the supermarket within two minutes.

They entered the building shortly after, and the scene was declared safe an hour later once it had been cleared and all the victims had been located.

An eyewitness - who was wearing a Walmart uniform - described what happened in footage that circulated on social media shortly after the attack.

He said he had left a staff room, which a colleague then entered before quickly opening fire. "Sadly we lost a few of our associates," he said.

Walmart said it was "shocked at this tragic event" and was "working closely with law enforcement". President Joe Biden described the attack as "another horrific and senseless act of violence".