Three security guards have been arrested over the death of a man on a plane at Heathrow Airport, as he was being deported from the UK to Angola.
Jimmy Mubenga, 46, was being escorted on to a British Airways flight by staff from the private firm G4S on Tuesday.
Passengers said he had been restrained and was struggling to breathe.
Three male G4S employees, aged 35, 48 and 49, have been questioned by the Metropolitan Police. They were released on police bail until December.
Labour MP Keith Vaz, who chairs the Home Affairs Select Committee, has described it as a "shocking" matter and called for "a full-ranging inquiry" into what happened.
Tom Brake, the Liberal Democrat MP for Carshalton and Wallington, has said he wants the case to be debated in Parliament.
Mr Mubenga's 16-year-old son Roland said on Friday he was "angry and upset" and claimed "it wasn't a natural death".
A second post-mortem test is to be held as the cause of his death remains unclear.
An inquest into Mr Mubenga's death - described by police as "unexplained" - is expected to open later this week.
G4S said in a statement that three employees were "continuing to help the police with their investigation".
"As a result of that ongoing investigation we are unable to provide additional comment at this time."