Homicide detectives are investigating after a 47-year-old Melbourne man died in the back of an ambulance.
The man had been found at an intersection in Gardenvale, in the city's south, on Wednesday evening after police received a report that he wanted to harm himself.
An officer escorted the man into an ambulance.
He was then treated by paramedics but died while still en-route to hospital, a police spokeswoman said.
The homicide squad and the professional standards unit have been called in since the man died in the presence of a police officer.
A cause of death is not known.
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