The police watchdog is investigating after a man died following attempts to restrain him.
The Independent Police Complaints Commission (IPCC) said staff at Medway Maritime Hospital in Gillingham, Kent, called police at about 12.45pm on Monday to a report that a 52-year-old man being held there under Section 2 of the Mental Health Act was missing.
Two police officers were sent to the man's home address in Goudhurst Road in the town.
They arrived at about 1.30pm and found the man there.
An IPCC spokeswoman said: "At this stage it appears that, while officers were attempting to restrain the man, he became unwell.
"An ambulance was called but the man was pronounced dead at the scene a short time later.
"The case was referred to the IPCC and a decision has been taken that the case will be independently investigated.
"IPCC investigators are currently at the scene gathering information."