POLICE IN THE United States have shot and killed a black teenager on Tuesday afternoon in the city of Columbus, Ohio.

Bodycam footage screened at a news conference showed an officer shooting the girl as she appeared to attempt to stab two people with a knife.

A black-handled blade resembling a kitchen knife or steak knife appeared to be lying on the footpath next to her immediately after she fell.

Officers had responded to an attempted stabbing call when police shot the girl at about 4.45pm local time, police said. The emergency caller reported a female was trying to stab them before hanging up, they said.

The girl was taken to a hospital, where she was pronounced dead, police said.

It was unclear whether anyone else was injured.

“This afternoon a young woman tragically lost her life,” Columbus Mayor Andrew Ginther tweeted.

He later said at the news conference: “We know based on this footage the officer took action to protect another young girl in our community.”

A crowd had gathered Tuesday night at the scene, which police had partially blocked off to traffic.

Others gathered at the city’s police headquarters to protest, a week after officers pepper-sprayed a group that tried to enter the headquarters over the police killing of a man who had a gun in a hospital emergency room.

Hundreds of protesters pushed past police barriers outside the headquarters and approached officers as city officials were showing the bodycam video inside.

Many chanted “say her name”, while others yelled “she was just a kid”.

Officers with bicycles pushed protesters back and threatened to deploy pepper spray on the crowd.

The girl’s name and age were being withheld while her family was notified, police said.

The shooting happened some 25 minutes before a judge read the verdict convicting former Minneapolis police officer Derek Chauvin of murder and manslaughter in the killing of George Floyd.