Updated

Four British men who spent up to three years in U.S. custody at Guantanamo Bay (search) and then held by British police for a day were released Wednesday night without charge.

Moazzam Begg, Feroz Abbasi, Martin Mubanga and Richard Belmar were returned to Britain on Tuesday and arrested under the Terrorism Act (search).

Metropolitan police questioned the four most of the day Wednesday but announced shortly after 9 p.m. that no charges would be filed.

Five other British detainees atere returned in March were also set free within a day, and have never been charged with a terrorist offense.

There was no announcement of where the men were going next.

Metropolitan Police Commissioner Sir John Stevens (search) had said it was unlikely that any of the men would be charged unless they admitted an offense. Any confessions made at Guantanamo would not be admissible in a British court, Stevens said in an interview with The Independent newspaper.

"If an admission is made, it is a totally different ball game. If they go to court it could be used as evidence," Stevens was quoted as saying.

Some of the men claimed they were tortured at Guantanamo, which holds detainees that U.S. authorities say are suspected of having links to Al Qaeda (search) or Afghanistan's ousted Taliban regime.

"They have been imprisoned in cages," said Louise Christian, who represented Abbasi and Begg. "Feroz Abbasi and Moazzam Begg have been held in solitary confinement for nearly two years and we know they have been tortured and abused."

U.S. government documents released last month showed that FBI agents sent to Guantanamo in 2002 reported some interrogators were being abusive, inserting lit cigarettes in prisoners' ears and shackling them into a fetal position for hours. U.S. officials says the incidents occurred in 2002, and some "aggressive" interrogation techniques have been stopped.

Their release followed months of negotiations between Washington and London to address U.S. security concerns. Prime Minister Tony Blair's (search) government had argued that the men should face a trial that met international legal standards, or be sent home.

The four Britons were among some 550 prisoners from 42 countries swept up in the U.S.-led war on terror and detained without charge.

Abbasi, 24, was reportedly arrested by U.S. forces in northern Afghanistan in December 2001. Belmar, 25, and Begg, 37, were arrested in Pakistan in February 2002, and Mubanga, 32, was detained in Zambia.

The Pentagon said British authorities had given assurances "that the detainees will not pose a continuing security threat to the United States or its allies."