Campaigners trying to prevent the deportation of Isa Muazu are pinning their hopes on a last-minute court injunction which will be sought tonight, just hours before the Nigerian national is due to be returned to his home country.
Muazu weighs just 50 kilograms after going 90 days without eating and is no longer able to see or stand, but he is due to be deported to Nigeria tomorrow despite claims he will be killed by Islamic extremists if he returns to the country.
Tonight's court injunction will be based on the health threat posed by the use of restraints on high-risk individuals.
It is understood that the use of restraints against pregnant women has previously led to successful injunctions.
In a separate move, a new immigration claim is being made in parallel to the injunction.
The claim would fight the Home Office's original rejection of Muazu's asylum, which was based on the twin arguments that there was sufficient police protection and a potential for relocation in Nigeria.
Today, a Home Office doctor conducted a reassessment of Muazu, which could provide a lifeline to the asylum seeker.
Details of the assessment have not yet been released. If it finds him unfit to fly, tomorrow's deportation could be cancelled.
Dozens of protesters are expected to hold a candle-lit vigil outside the Home Office at 17:30 GMT tonight.
Actor Lucy Ellinson will deliver a letter to the Home Office signed by over 100 actors and human rights groups demanding it cease the deportation.
Liberal Democrat peer Lord Roberts sent another letter to Theresa May demanding that she take action.
The letter reads: "Mr Muaza's condition is critical. He has been on hunger strike in Harmondsworth Detention Centre for almost 100 days, and is no longer able to see or stand.
"We are extremely concerned that Mr Muaza will soon die or suffer permanent damage to his health in detention - or during a forced removal from the UK, scheduled for tomorrow morning.
"I call on you to exercise clemency and I ask other colleagues to do the same.
"You, personally, are able to avert death, or serious harm, in detention or during the removal process. Please do so, today."
Lord Roberts has put in three private notice questions trying to force a discussion of the deportation in the Lords, but authorities consider the matter sub-judice, meaning it cannot be discussed because it is the subject of an ongoing legal matter.
A similar fate has befallen Liberal Democrat MP Julian Huppert's efforts to force an urgent question in the Commons.
The Home Office refuses to comment on individual cases.