A defendant in an Old Bailey terror trial broke down in the witness box as he was questioned about claims he was tortured by Pakistani security forces.
Mr Amin (bottom left) broke down in the witness box
Salahuddin Amin said he was forced to make a confession about sending co-defendant Omar Khyam the formula for an explosive device.
He said his interrogators threatened to "drill another hole in his backside".
Mr Amin, 31, from Luton, Bedfordshire, and six others deny conspiring to cause explosions likely to endanger life.
His co-defendants were arrested after 600kg of fertiliser was found at a storage depot in Hanwell, west London, in March 2004.
Mr Amin handed himself into Pakistani authorities in April 2004, but was held without charge for 10 months before he was flown back to Britain, where he was arrested and then charged.
'Beaten with truncheons'
He said he gave himself up to the Pakistani security services - the ISI (Inter-Services Intelligence) - in April 2004 on the advice of his uncle, an former brigadier in the Pakistani military.
He said he was taken to an ISI facility in Rawalpindi and held in a small room with bright lights. He said he was beaten with truncheons.
Police found 600kg of ammonium nitrate in a west London lock-up
His barrister, Patrick O'Connor QC, said: "Was something else used on you?
He replied: "After a while they told the guards to get a drill machine."
Mr O'Connor said: "Were you told to do anything?"
"They plugged it in, then it would not work. Then he shouted at the guard. Then he told me to lift my kameez (shirt) up," Mr Amin said.
Mr O'Connor asked: "Where were you facing?"
"The wall," he said.
"What did they do?" asked Mr O'Connor.
"(The office) said to (the other man) 'Drill another hole in his backside'," he said.
"Did you hear the drill working?" he asked.
"He came to me and he touched me and now I believed it was not the drilling machine because I did not feel pain. But he touched me with something but it must have been his finger or something. I was extremely scared."
"Did you believe for a moment the drill was going to be used to penetrate into you?"
"Yes," he replied.
"How did you react to that?"
"I broke down and started crying and I said 'Sorry, I will agree with everything you want'."
He said the confessions he subsequently made - and repeated to British police - were false and made under duress.
Seven men deny conspiring to cause explosions likely to endanger life between 1 January 2003 and 31 March 2004.
They are Omar Khyam, 25, and his brother Shujah Mahmood, 19, both from Crawley, West Sussex; Waheed Mahmood, 34, and Jawad Akbar, 23, also of Crawley; Salahuddin Amin, 31, from Luton, Bedfordshire; Anthony Garcia, 24, of Barkingside, east London; and Nabeel Hussain, 21, of Horley, Surrey.
Mr Khyam, Mr Garcia and Mr Hussain deny a further charge under the Terrorism Act of possessing 1,300lb (600kg) of ammonium nitrate fertiliser for terrorism.
The brothers also deny possessing aluminium powder for terrorism.