Posted date: 2013-08-21 04:14:23
A Brazilian man held for nine hours at Heathrow airport under anti-terror laws has said he was forced to divulge email and social media account passwords.
David Miranda said his interrogators threatened that he could go prison if he did not do so.
Mr Miranda is the partner of Guardian journalist Glenn Greenwald who has covered stories based on leaks by US whistle-blower Edward Snowden.
Mr Miranda has launched legal action over the use of the powers on him.
He wants his confiscated electronic equipment returned and assurances that his private data will not be distributed on to other parties.
Mr Miranda told the BBC that disclosing his passwords made him feel as if he were "naked in front of a crowd".'Entire life'
A Downing Street spokesman has said Number 10 was "kept abreast" of the decision to detain Mr Miranda, 28, who was held on Sunday on his way from Berlin to Rio de Janeiro where he lives with Mr Greenwald.
The Guardian said he had been carrying "journalistic materials" but was not an employee of the newspaper.
Mr Greenwald has broken stories about state surveillance with information from fugitive Mr Snowden who used to work as a contractor at the US National Security Agency.
Mr Miranda said he was held in a room and questioned by six agents about his "entire life".
His lawyers said they confiscated his laptop, an additional hard drive, two memory sticks, a mobile phone, a smart watch and a video games console.
Mr Miranda was detained under schedule 7 of the Terrorism Act 2000.
This allows police to hold someone at an airport, port or international railway station for up to nine hours for questioning about whether they have been involved with acts of terrorism.'Stolen information'
His law firm Bindmans has written to Home Secretary Theresa May and the Metropolitan Police commissioner for assurances "there will be no inspection, copying, disclosure, transfer, distribution or interference, in any way, with our client's data pending determination of our client's claim".
Mrs May said the police must act if someone had "highly sensitive, stolen information".
Scotland Yard maintained the detention was "legally and procedurally sound".
Meanwhile, it has emerged that Prime Minister David Cameron ordered Britain's top civil servant, Cabinet Secretary Sir Jeremy Heywood, to contact the Guardian about material it had obtained from Mr Snowden.
The discussions resulted in the newspaper destroying computer hard drives storing the information, under the supervision of intelligence experts from GCHQ.
The files had already been copied and the Guardian will continue to pursue the Snowden story, but from the US. Mr Snowden is now based in Russia.