An inquiry is underway after a man awaiting deportation died in mysterious circumstances at a privately run immigration detention centre in west London.
The death occurred on Tuesday night at the Harmondsworth immigration centre near Heathrow Airport - a 615 bed facility run by GEO Group UK Ltd.
The company and the Home Office have so far refused to give any information about the man's death - his name and nationality have not been disclosed.
The Prisons and Probation Ombudsman confirmed that an investigation had been opened but said the name of the deceased was yet to be confirmed.
A PPO investigator will visit the detention centre next Tuesday.
The death has been referred to the Hillingdon coroner but an inquest is not expected to open until the middle of next week.
There have been six deaths at Harmondsworth since 1989. GEO declined to tell The Independent whether any staff members had been removed from their duties following the death.