Eric Harris shooting Tulsa
Tulsa County authorities released a video showing suspect Eric Harris being shot dead.YouTube

An Oklahoma policeman is seen shooting a man dead by accident in a video released by authorities, after mistaking his handgun for a stun gun .

The clip is the latest in a series of fatal incidents involving black Americans finding their death at the hands of white police officers that has caused tensions and protests across the US.

The recording from a Tulsa County officer's sunglasses camera shows police chasing Eric Harris, a 44-year-old who had allegedly tried to sell an illegal gun to an undercover detective.

As Harris is tackled to the ground a deputy is heard telling him: "I need you to roll on your stomach," while a female onlooker urges everyone to "Stop fighting".

Moments later a bang is heard. "Oh, I shot him. I'm sorry," a man identified as 73-year-old reserve deputy Robert Bates says.

The suspect then screams: "He shot me. Oh my God," and a deputy replies: "You f***ing ran. Shut the f*** up."

The video ends with Harris saying he is losing his breath to which a deputy replies, "F*** your breath."

WARNING graphic video

Harris was taken to a local hospital where he later died. Tulsa County Sheriff's Office said Bates intended to incapacitate Harris using a stun gun as he was being subdued, but accidentally took hold of his pistol and fired that instead.

A Tulsa Police Sergeant who investigated the shooting said Bates suffered a stress-induced phenomenon known as "slips and capture", which led him to believe he was holding a Taser when opening fire.

Prosecutors are now to decide whether to file criminal charges. The clip of the 2 April 2015 incident was released by the Tulsa County Sheriff's Office after a request by Harris's family that it be made public.

It comes just days after a bystander filmed South Carolina officer Michael Slager shooting unarmed suspect Walter Scott eight times in the back, as he attempted to flee after being stopped because his car had a broken light.

The footage re-ignited nationwide outrage at police and their perceived excessive use of force against African-Americans that followed the killings Michael Brown, 18, in Ferguson, Missouri and Eric Garner, 43, in New York City.