AMERICA was warned yesterday that it faced a new “home-grown terrorist” threat after the FBI arrested seven men accused of conspiring with al-Qaeda and plotting to blow up the Sears Tower in Chicago.

The alleged terrorist cell was said to have been based at a warehouse in Liberty City, Miami, where they wore turbans and dressed in black while performing “military-style” training exercises outside.

Although law enforcement chiefs acknowledged that their plans were more “aspirational than operational”, the group, five US citizens and two Haitian immigrants, had been in contact with an FBI agent posing as a member of al-Qaeda.

According to a federal indictment, they vowed to “kill all the devils we can” by blowing up the 110-storey Sears Tower, America’s tallest skyscraper, and government buildings. A man identified as Narseal Batiste started recruiting and training the others in November “for a mission to wage war against the United States”.

He is alleged to have met the undercover FBI agent in December and asked for bulletproof vests, machineguns, radios, vehicles and $50,000 (£27,500) for Islamist attacks intended to be “as good as or greater than 9/11”.

FBI chiefs emphasised that the men arrested in Miami did not constitute an immediate threat to the US but had been arrested as a pre-emptive strike to stop them acquiring the means, as well as the will, to commit a terrorist attack. But last night relatives disputed police claims that the group, known as the Seas of David, was dangerous. Some said that it was not even Islamic, saying the men’s beliefs were based on Christianity.

Alberto Gonzales, the US Attorney-General, told a news conference: “They were persons who, for whatever reason, came to view their home country as the enemy.” He said that they were examples of a home-grown phenomenon which, as had already been seen in London and Madrid, “may prove to be as dangerous as groups like al-Qaeda”.

Robert Mueller, the FBI director, also cited the attacks on London last year as he warned the US to brace itself for the enemy that “operates under the radar screen” and comes from “our own streets”. In a speech in Cleveland, he said that Islamic radicals were being recruited as terrorists in prisons, schools and universities and from the 5,000 to 6,000 extremist websites on the internet. Cells in Lackawanna, New York, Portland, Oregon, Torrance, California and now Miami had been disrupted.

The US has taken pride in the contrast between the relatively harmonious relations with its Muslim population and Europe’s racial divisions.

Recent congressional hearings on the issue focused on the threat of terrorists coming from Europe and the “tolerance of intolerance” in multicultural capitals such as London.

Daniel Benjamin, a former White House adviser who is now a terrorism watcher at the Centre for Strategic and International Studies, said: “In the United States we have only had a couple of dozen arrests for terrorist offences. In Europe, the numbers are in hundreds and possibly thousands.” He quoted a Home Office estimate of 10,000 to 15,000 British Muslims who actively support al-Qaeda or related groups. But The Times has learnt that for all such displays of complacency, US intelligence agencies have begun to bug mosques and Islamic centres.

The FBI has sent undercover agents and paid informants to infiltrate militant mosques where young Muslims have reportedly been setting up terrorist cells.

In May a federal court in Brooklyn convicted Shahawar Matin Siraj, 22, of plotting to bomb a Subway station in Manhattan in 2004, timed to coincide with the Republican Party convention in the city. Siraj had been living in Queens for six years and, police say, had no known connection to any overseas terror group.

“This was a New York plot by an adopted New Yorker to harm his adopted city,” a New York police spokesman said.

Hussein Ibish, the executive director of the Foundation for Arab-American leadership, said that US Muslims were generally better off, more assimilated and spread out more widely across the country than their European counterparts. “But this has bred a sense of comfort and superiority which may be setting itself up for disappointment.”

There were angry, alienated young men in Muslim communities, he said, who were attracted to jihadist ideologies. “If they are going to do something crazy then it’s obviously right that the Government should be aggressive in the way that it investigates them.

“It’s important to point out that the key information for the police is coming from within the community.” But Mr Ibish said that such co-operation could be threatened by the way US law enforcement agencies worked.

“It becomes close to entrapment to find an alienated young man and feed him violent ideas to see if he is a terrorist,” he said.

ON THE INSIDE

In none of these cases has there emerged any known link to Osama bin Laden nor any apparent funding from al-Qaeda operatives overseas

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