A man with British and Pakistani nationalities has been arrested in Islamabad on suspicion of having links with the Al Qaeda.

Tariq Mahmud, in his 30s and from Birmingham, was arrested during a search and capture operation involving Pakistani and US intelligence officials.

Sources in London say Mahmud, who has two children, left the UK several years ago and is believed to have moved to Islamabad after spending time in Afghanistan.

After he was captured on Wednesday night, he was taken for interrogation to the Bagram detention centre outside Kabul, where US forces have a base.

This is the second time that Pakistani and US special forces have collaborated against a Pakistani national. Moazzem Begg, who lived in Birmingham, was arrested when he visited Pakistan.

In London the foreign office said, "We are aware of reports of an arrest of a British national in Pakistan. Our consular staff are making enquiries with the Pakistan Ministry of Foreign Affairs. We are in touch with next of kin."

According to British sources Mahmud might be questioned about possible links with Begg. Both men could end up at the US interrogation centre in Guantanamo Bay.