Anti-terrorist police across western Europe have combined to arrest at least 20 people suspected of being involved in terrorist activity. Two men were arrested in Britain, the others in northern Italy, France and Portugal. Police believe they were recruiting and assisting suicide attackers in Iraq and Afghanistan. The operation included security forces from Italy, Britain, France and Portugal. Italian police said they seized poisons, detonators, instructions on guerrilla warfare, and pilot manuals for a jumbo jet.