An al Qaida terror suspect was beaten so badly by police he thought he was going to die, a court has heard.
Babar Ahmad, 37, told Southwark Crown Court he was beaten up in his home, in a police van and at a London police station.
He said one officer twice put him in a headlock while they were en route from his semi-detached home in Fountain Road, Tooting, London, to Charing Cross police station.
Mr Ahmad, giving evidence against four officers from the Metropolitan Police's Territorial Support Group, said he was made to lie down in the van with his wrists handcuffed behind his back.
He said one officer straddled him and swore at him, saying: "You will remember this day for the rest of your life." Mr Ahmad added: "He squeezed and kept on squeezing. I remember the pressure to the side of my neck. He squeezed and squeezed and squeezed and held it in that position.
"I thought he would hold it for a few seconds and if I hold my breath I could bear it and he would let go. But he didn't let go. I kept thinking 'He is going to stop, he is going to stop, he is going to stop.' I was panicking because I couldn't do anything or move.
"It's like drowning. There is nothing you can do. He kept squeezing to the point where I thought 'This guy is going to kill me. 'He wants to kill me. I am going to die in the back of this van.'"
Police smashed into the IT worker's home at 5am on December 2 2003 to arrest him on suspicion of terrorist involvement. No charges came of the arrest. Mr Ahmad is awaiting extradition to America where the authorities want him over alleged terrorist involvement.
He told the jury of seven men and five women that the officers repeatedly punched him all over the body, stamped on his bare feet, gripped his privates, and twisted the loose handcuffs around his arms.
Police constables Roderick James-Bowen, 40, Mark Jones, 43, Nigel Cowley, 34, and Detective Constable John Donohue, 37, all deny assault.