British Prime Minister Tony Blair says his countrymen must be as vigilant as British security forces for a possible attack by international terrorists.
Mr. Blair told his monthly news conference Tuesday the Islamic terrorist threat is real, but the British public is well prepared to deal with it, given their experience with Irish republican violence.
"People in Britain, because of our experiences in the past, I think know that we should remain vigilant but calm in the face of terrorism and determined to defeat it," he said. "And I think that is the general attitude of most people. And our security services, our intelligence services, our police, do a magnificent job in protecting us, but of course we've got to remain permanently vigilant."
As the prime minister spoke, police were questioning 14 people arrested in three separate anti-terrorism raids early Tuesday.
Four men detained in London were suspected of what a police spokesman called "the commission, preparation or instigation of a terrorist attack."
In the university city of Cambridge, police say they arrested four men and two women also suspected of plotting an act of terrorism.
And police say four other men were picked up under the British anti-terrorism law in the towns of Dudley and Walsall, near the central English city of Birmingham.
Last week, police in the southwestern town of Gloucester arrested a 24-year-old man suspected of planning a suicide bombing. He has not been charged but remains under questioning. The government's Home Office says the man has suspected links to the al-Qaida terrorist network.
British intelligence officials warned two weeks ago a possible terrorist attack was being planned, and the country remains on its highest state of alert short of an actual attack in progress.