The threat of a terrorist attack on European soil by Islamic radicals has increased substantially in recent months, reaching its highest levels since the London transit attacks of July 2005, according to European counterterrorism officials. Adding to the anxiety: fresh threats against Britain and France delivered Wednesday by al-Qaeda's deputy leader.
In a new videotape, Ayman al-Zawahiri, the second-in-command to al-Qaeda chief Osama bin Laden, singled out Britain as a historical enemy of Muslims, blaming it for the creation of the state of Israel and the downfall of the Ottoman Empire in the early 20th century.
He also said al-Qaeda would continue to plan attacks on the United States and its "Crusader" allies in Europe as long as Western powers remain in Iraq, Afghanistan and Lebanon. "The animosity of Britain toward Islam stretches over centuries," Zawahiri said, according to a translation of his remarks by the SITE Institute, a terrorism research organization. "Isn't it the one who used to occupy most Islamic lands?"
It was the 15th recorded speech released this year by Zawahiri, a 55-year-old Egyptian physician who has shown little fear of speaking out despite a $25 million reward for his capture posted by the U.S. government.
Frequently wagging a finger to make a point, he spoke with a rifle displayed in the background. "I tell both the Republicans and Democrats . . . you try to negotiate with certain parties to secure your departure, although the parties don't have a way out for you" from Iraq. "You shall come back -- Allah permitting -- with no other choice but to negotiate with the real powers," an apparent reference to al-Qaeda's wing in Iraq.
U.K.: 'Highly likely'
Zawahiri's remarks followed a raft of general warnings by authorities in Britain, France and Germany that major attacks might be coming. They have given no specifics.
Last week, British Home Secretary John Reid declared that an attempted terrorist strike in his country was "highly likely" over the Christmas and New Year's holidays. There has not been a major terrorist attack in Europe since the July 7, 2005, bombings in London. But European counterterrorism officials have disrupted dozens of attempts since then and have far more suspected radicals under surveillance now than at any point since the Sept. 11, 2001, hijackings in the United States.
In November, the director general of Britain's MI5 intelligence service, Eliza Manningham-Buller, said the agency was tracking more than 1,600 members of suspected terrorist cells, more than triple the number under surveillance three years ago. Manningham-Buller, who rarely speaks in public, said investigators were monitoring about 30 major terrorism plots in the planning stages.
"The threat has really proliferated," said M.J. Gohel, chief executive of the Asia-Pacific Foundation, a London-based security research organization. "One of the reasons why Western intelligence and counterterrorism officials are so concerned is because they have unraveled so many plots involving so many different independent cells."
Other European countries have been on heightened alert. Spanish investigators broke up a cell of Islamic militants last week that was allegedly plotting attacks on an arms depot and a supermarket.
On Friday, Germany's chief federal prosecutor, Monika Harms, said that "the threat posed by Islamist terrorism must not be underestimated" in that country, citing an alleged plot to blow up regional trains with suitcase bombs in July and a separate scheme to smuggle explosives onto an Israeli airliner at the Frankfurt airport.
Intelligence officials and analysts said the number of European Muslims who have become radicalized has escalated in recent years, especially since the Iraq invasion and the wars in Lebanon and Afghanistan. But they also cited factors closer to home, including rising anger among immigrants and later-generation Muslims who feel marginalized in European society.
Zawahiri's recent remarks have particularly concerned French counterterrorism officials. They have warned of a heightened risk of attacks because of a newly declared alliance between al-Qaeda and an Algerian-based network, the Salafist Group for Preaching and Combat, which has developed an extensive collection of cells in France and elsewhere in Europe.
In September, Zawahiri announced the formation of the partnership and urged the Algerian network to become "a dagger in the hearts of the French traitors and apostates." On Wednesday, he repeated the command, predicting that the Algerians would soon defeat the "secularist sons of France."
French officials said this week that they have arrested 76 suspected members of the Algerian network since June 2005 in connection with three separate plots, including alleged plans to bomb the Paris subway and Orly airport.
Jean-Louis Bruguiere, France's chief anti-terrorism judge, said that France had become "the main target" of the Algerian group and that the risk of attacks had increased over the past six months. "We consider the threat level to be very high," he said in an interview published Wednesday by the International Herald Tribune. "What is new is that this organization has formally pledged allegiance to al-Qaeda."
In his statement, Zawahiri also criticized the radical Palestinian movement Hamas for taking part in elections in January and failing to insist on an Islamic constitution. In earlier messages, he has called on Islamic fighters to go to the Palestinian territories to fight alongside Hamas.
Staff writer Karen DeYoung and researcher Julie Tate contributed to this report.