Matt Ratana shooting: Suspect Louis De Zoysa formally charged over death of Kiwi police officer in London

A man has been charged with murder in relation to the death of a Kiwi police officer in the UK.

Fifty-four-year-old Matt Ratana was shot at the Croydon Custody Centre in September. Louis De Zoysa, the 23-year-old suspect, was initially arrested for possession of class B drugs and ammunition - before he allegedly shot the officer.

The suspect was also hospitalised with a gunshot wound but his condition has since improved.

De Zoysa was formally arrested for the death of Ratana in September and was charged with murder on Tuesday, the BBC reported. He'll appear in court on Wednesday (local time).

"We have updated Matt's partner and son on this significant development," a Metropolitan police spokesperson told the state broadcaster.

Ratana was laid to rest in November. In addition to being an officer in London's Metropolitan Police for nearly 30 years, after moving to the UK from New Zealand in 1989, Ratana was the head coach of East Grinstead Rugby Club in West Sussex.

Before moving to the UK, he studied town planning at Massey University in Palmerston North. He also attended high school there.