Burka terror suspect Mohammed Ahmed Mohamed is seeking damages from the government in a human rights legal challenge involving allegations of torture.
Mr Mohamed, who was the subject of a Terrorism Prevention and Investigation Measure (Tpim), managed to dodge surveillance and disappear by disguising himself as a woman.
The 27-year-old was last seen fleeing a London mosque in the burka on Friday.
Mr Mohamed used a sharp instrument to cut off his electronic tag – imposed as part of a terrorism prevention measure.
The tag issued a “tamper alert” to its makers, the private security firm G4S who alerted officials, the BBC said.
The Met Police’s counter terrorism command, MI5 and the UK’s Border Force are looking for him.
Today Mr Justice Irwin handed down an interim ruling in the action he is bringing for compensation – the first ruling on the use of the Justice and Security Act 2013 in a civil claim for damages.
His claim is against the Foreign Office, Home Office, Ministry of Defence and the Attorney General.
Read more: Theresa May: escaped terror suspect poses no 'direct threat
He and another man, referred to as “CF”, allege the British authorities consented to – or acquiesced in – their detention by the Somaliland authorities on January 14 2011.
The men say British “officers and agents… by their acts and omissions, procured, induced, encouraged or directly caused, or were otherwise complicit in” their detention, assault and mistreatment and torture while they were in Somaliland.
Mr Mohamed launched his damages claim under a cloak of anonymity and was referred to in court papers as “MA”.
But anonymity was lifted today following his disappearance.
Channel 4 News has learnt more details surrrounding the escape in a burka of terror suspect Mohammed Ahmed Mohammed, writes Home Affairs Correspondent Simon Israel.
According to sources, it now appears that the 27-year-old removed his electronic GPS tracking tag, a crucial 15 minutes after he was caught on CCTV leaving the mosque in west London last Friday.
That raises speculation that he may have been on a tube train to Heathrow at the time he got rid of the device.
The Home Secretary Thersa May said this morning that their records show he was not in possession of a legal British passport since he arrived back in the UK in 2011 without one.
She said: “The police and security services have confirmed that they do not believe that this man poses a direct threat to the public in the UK. The reason he was put on a TPim in the first place was to prevent his travel to support terrorism overseas.”
The founder of a mosque where Mr Mohamed managed to dodge surveillance on Tuesday denied that anyone at the institution helped him escape.
He told Channel 4 News: “I completely refute that, because I do not understand why we, as the management of this institution, would condone such a thing.”
Mr Rashad said he saw Mr Mohamed – who had visited the centre before – in his normal clothes on Friday, the day he disappeared.
Read more: Inside the mosque of the burqa escapee
But he said he was unaware Mr Mohamed had an electronic tag and he had “not got a clue” about how or where he changed into the burka.
“I personally did not know what was going on, I am still in a state of shock from what has taken place in our centre,” he said.
Mr Mohamed is the second person to go missing while the subject of a Tpim.
Police have urged anyone who sees Mr Mohamed or knows of his whereabouts not to approach him but to call 999.
Somalia-born Mr Mohamed, who is 5ft 8in tall and of medium build, arrived at the An-Noor Masjid and Community Centre in Church Road, Acton, at 10am on Friday and was last seen there at 3.15pm that day.