A police officer killed in the line of duty at a custody centre died from a gunshot wound to the chest, an inquest has heard.

Metropolitan Police Sergeant Matt Ratana was shot in the early hours of Friday September 25 as he prepared to search a suspect who was handcuffed.

The 23-year-old suspect, who was not named during the 10-minute inquest opening at Croydon Coroner’s Court, was also injured and remains critically ill in hospital.

Detective Superintendent Nick Blackburn said the weapon was discharged “several times”.

A revolver was later recovered from the scene.

He told the inquest the suspect was first detained by police in Pollards Hill in south London at 1.30am.

The suspect was handcuffed and taken into custody on suspicion of the possession of ammunition and a class B drug.

He said: “Upon arrival (at Croydon custody centre), he (the suspect) was taken to a holding room where he remained in handcuffs.

“The custody sergeant, Matt Ratana, entered the holding room.

“The suspect discharged the weapon several times, during which the sergeant and the suspect were injured.”

The inquest heard Mr Ratana was taken to St George’s Hospital in Tooting but he was pronounced dead at 4.20am.

Mr Blackburn said the preliminary cause of death given following the post-mortem examination was a gunshot wound to the chest.

He said the police watchdog, the Independent Office for Police Conduct, is investigating.

He told the inquest: “This matter has deeply shocked and saddened all of us at the Met.

“But rest assured, the Met will conduct a thorough investigation.”

No members of Mr Ratana’s family, including his partner Su Bushby, were present for the hearing, although Mr Ratana’s son in Australia was among those listening in remotely.

Sarah Ormond-Walshe, senior coroner for south London, adjourned the hearing until a further date.

The inquest opening followed a tribute by New Zealand’s high commissioner to the UK at Croydon Custody Centre on Thursday morning.

Bede Corry joined Metropolitan Police Commissioner Dame Cressida Dick to pay his respects at a makeshift shrine, laying a wreath in front of the sombre memorial, which was bedecked with scores of floral bouquets, and surrounded by New Zealand flags and sports jerseys.

Mr Corry said in a statement: “New Zealanders were shocked and saddened to learn of the tragic death of Sergeant Matiu Ratana.

“We came today, to the place where he died, to share our grief and convey our condolences to the Metropolitan Police Service and through them, to Matiu’s family.

“As someone who was a police officer in New Zealand and the United Kingdom, he uniquely served both countries. We know he will be deeply missed.

“The High Commission will continue to support the Metropolitan Police Service as they assist Matiu’s family.”

The suspect is widely reported to be 23-year-old Louis De Zoysa.