Authorities on three continents are pooling their resources in a worldwide investigation into an alleged plot to blow up U.S.-bound flights from Britain.
British and Pakistani officials have detained more than 30 people suspected of planning to detonate liquid explosives aboard as many as 10 airliners.
Twenty-three of the suspects are Britons of Pakistani descent who have been under arrest since Thursday in London. One of them is described as the brother of a British man Rashid Raulf being held in Pakistan. Authorities there say he is a key figure in the investigation with links to al-Qaida in Afghanistan.
Investigators say police began rounding up suspects after someone in Pakistan called conspirators in Britain and urged them to immediately carry out their plan.
Still at large is a Pakistani man suspected of being an al-Qaeda operative.
American counter-terrorism officials say hundreds of FBI agents are looking for possible U.S. ties to the conspiracy. They are combing through calls that British suspects made to the U.S.
A coalition of British Muslim groups and politicians said Saturday that Britain's foreign policy on Iraq and Lebanon is fueling extremism that threatens all civilians. In an open letter to British Prime Minister Tony Blair, the coalition urged the government to do more to fight terrorism, while taking care not to target innocent civilians.
The British government rejected the accusation.