British police claim to have thwarted an al Qaeda plot involving Pakistani nationals.
Twelve men - 11 of them Pakistanis - were arrested in a major counter-terrorism operation involving nine raids by hundreds of officers in northwest England, the police said on Friday.
Prime Minister Gordon Brown says he spoke with President Asif Ali Zardari of Pakistan by telephone on Thursday night to discuss the operation.
Mr Brown says that most terrorist plots identified in Britain by the security forces have originated in Pakistan, and that instructions are clearly coming from militant leaders based there.
Most terrorist plots in Britain since 11 September 2001 have had links to Pakistan, including the suicide bombings of 7 July 2005 that killed 52 people on the London underground and bus network.
Confirming that a 10th address, in Liverpool, was also being searched, the police in Manchester said that the suspects so far arrested were in custody "in various locations across the country".
