LONDON, May 12: A secret interrogation centre in Pakistan where British terrorism suspects are alleged to have been tortured after UK authorities had them arrested has been found by the Guardian.

A report in the newspaper on Monday said the centre, run by the country’s Inter-Services Intelligence agency (ISI), is in the Saddar district of Rawalpindi. It is surrounded by high walls and watchtowers, and bristling with surveillance cameras.

The report also carries an aerial photograph of the interrogation centre.

A British citizen is quoted as saying he was driven there in 2004, held for 10 months and tortured. Salahuddin Amin, now aged 33, had moved to Pakistan three years earlier from Luton, Bedfordshire. He was eventually returned to the UK and successfully prosecuted.

A second British citizen, aged 33 and from Manchester, who was arrested at the request of British authorities, is thought to have been held at the same place. Two other British citizens have said they were tortured by the ISI before being questioned by British counter-terrorism officials.

MI5 declined to comment, but pointed to evidence given to the all-party intelligence and security committee about training it gives its agents regarding the possible mistreatment of detainees by foreign intelligence agencies. Guidance for officers questioning detainees held overseas states: “The security and intelligence agencies do not participate in, solicit, encourage or condone the use of torture or inhuman and degrading treatment.”

Asked about this failure, the Foreign Office said it could not act for British citizens of joint British-Pakistani nationality, as the authorities in Islamabad regarded them as being only Pakistani.

The Foreign Office would not say how many British citizens have been detained in Pakistan in the last decade and questioned over alleged terrorism. Nor would it disclose how many had subsequently complained of mistreatment, saying: “We have a duty to respect the privacy of the individuals concerned.”

Asked how many complaints of mistreatment had led to investigations by British authorities, the Foreign Office replied: “None. The British authorities are not able directly to investigate the conditions in Pakistani institutions.”