An investigation has been launched into a death in police custody at a Coles supermarket on Tuesday.

An adult man stopped breathing while being restrained by two Northern Territory Police officers inside a shopping centre in the Alice Springs CBD at about 1.10pm.

Police said the man had been “involved in an altercation with a security guard at the Coles supermarket” before being taken into custody.

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Officers provided CPR after the man stopped breathing, and St John Ambulance was called to the scene.

Paramedics took the man to Alice Springs Hospital, where he was declared dead shortly after 2:20pm.

The shopping centre was closed, and a crime scene was established.

Detectives from the NTPF Major Crime Section are travelling to Alice Springs to investigate.

A report will be prepared for the coroner.

Witnesses are urged to contact Crime Stoppers.