This is the moment two police officers shoot and kill an elderly homeless man who ran at them with a small knife in hand after they unsuccessfully tased him.

The incident took place in the middle of a road in the city of Nashville, in the US state of Tennessee, after local residents made a report to the police about the man, later identified as Drandon John Brown, 64, throwing rocks at cars.

Officers soon arrived at the scene and encountered Brown by the side of the road and attempted to speak to him.

This body-worn footage that was obtained by Newsflash shows officers trying to reason with Brown, who they had a hard time communicating with as he mostly rambles without making sense.

Then he pulled out a small knife and ran towards them, the police said.

They failed in an attempt at tasing him and Brown charges towards them whilst holding the knife.

And that is when one of the officers shot Brown, who died at the scene.

None of the involved officers was injured, the police said.

Brown reportedly lived in a homeless encampment in Nashville.

He allegedly suffered from severe mental illness but refused to receive help.