LONDON, United Kingdom (AFP) — A UK police officer went on trial on Wednesday charged with the murder of a black man in London two years ago.

Firearms officer Martyn Blake, 40, denied a charge of murdering Chris Kaba, 24, who was shot in the head on September 5, 2022.

Prosecutors told the Old Bailey court the shooting was “not reasonably justified or justifiable”.

Kaba was struck by a single gunshot fired into the vehicle he was driving in the Streatham area of south London.

His car, which was linked to a firearms incident the previous day, was being followed by police at the time, and forced to a stop.

A jury heard that Kaba was trying to drive away from police when the incident occurred.

However, the prosecution claimed there was “no real or immediate threat to the life of anybody present at the scene”.

“There can be no doubt you may think that the defendant must have intended to incapacitate the driver of the vehicle… He shot him once straight to the head,” said prosecution lawyer Tom Little.

“He was trained to use a firearm and, if necessary, to shoot knowing that almost inevitably death would follow, and that is what he did.”

Police in England, Scotland and Wales are not routinely armed and only a small proportion are authorised to carry guns.

Police prosecutions are rare and when London police announced Blake was being charged last year, dozens of his colleagues stepped back from firearm duties in protest.