The police officer killed by a suspect inside a London police station was shot in the chest, an inquest has heard.
Croydon Coroner's Court was told how SergeantMatt Ratana, 54, was preparing to search the handcuffed suspect at the time.
The suspect, who was not named at the hearing but is reported to be 23-year-old Louis De Zoysa, had been detained by police in Pollards Hill in south London at 1.30am on Friday.
He was handcuffed and taken into custody on suspicion of the possession of ammunition and a class B drug, the court heard.
Detective Superintendent Nick Blackburn said: “Upon arrival [at Croydon custody centre], he 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.”
Det Supt Blackburn said a revolver was later recovered from the scene.
The inquest heard Mr Ratana was taken to St George's Hospital in Tooting but he was pronounced dead at 4.20am.
The preliminary cause of death given following the post-mortem examination was a gunshot wound to the chest.
The Independent Office for Police Conduct is investigating the course of events that led to the suspect being able to retain and discharge the gun following his arrest.
Det Supt Blackburn 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 later date.
The murder investigation continues, with police searching crime scenes, carrying out enquiries on the suspect and examining video footage.
The inquest was opened following 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.”
Additional reporting by PA