LONDON — Yusuf Islam, the British singer once known as Cat Stevens, returned to London on Thursday saying he was "totally shocked" that U.S. officials who barred him from entering the United States on Tuesday considered him a potential terrorist threat.
Britain's foreign secretary, Jack Straw, formally criticized Washington's handling of the matter. The popular London-born folk singer, who converted to Islam in the 1970s, had frequently toured in the United States at the height of his career, and even as recently as May.
Islam said he hoped that U.S. officials would acknowledge they made "a big mistake."
On Wednesday, a spokesman for the Department of Homeland Security, Brian Doyle, said that Islam was deported because his name was on a "no-fly" list, Reuters reported, and because of activities that could potentially be linked to terrorism.
"The intelligence community has come into possession of additional information that further raises our concern," Doyle said, adding, "It's a serious matter." The department declined to specify further.
The vague nature of the accusation by U.S. intelligence and officials of the Department of Homeland Security clearly frustrated British officials, who said they had no information that Islam, a British citizen, was a threat to anyone or had any connection to terrorist groups.
Islam, 56, has spoken out repeatedly against violence since the Sept. 11, 2001, attacks on the United States, and has donated funds from his music royalties to the victims of those attacks.
Writing in The Guardian newspaper in 2001, Islam said: "Sadly, the latest horror to hit the U.S. looks to have been caused by people of Middle Eastern origin, bearing Muslim names. Again, shame. This fuels more hatred for a religion and a people who have nothing to do with these events."
A statement on Islam's Web site on Thursday said: "He has vehemently and consistently criticized terrorist acts and has always advocated peace through his songs and his extensive humanitarian relief work. He travels often to the United States, most recently two months ago on a visit with his record company.
"Any suggestion, therefore," the statement added, "that he poses a security risk due to alleged connections with terrorist activities is totally denied as it is simply wrong."
Foreign Office officials said that Straw, in New York for the U.N. General Assembly meeting, raised the matter with Secretary of State Colin Powell, telling him that Islam should not have been denied entrance to the United States.
The singer's London-to-Washington flight on Tuesday on a United Airlines Boeing 747 was ordered diverted to Bangor, Maine, where he was detained by FBI agents. He was traveling with his daughter, Maymanah, 21, who was allowed to stay in the United States.
The next day, United Airlines and homeland security officials blamed each other because Islam was allowed on the flight even though his name is on a terrorism watch list.
Islam had been quoted in the past as making contradictory statements about Muslim matters.
As Cat Stevens, Islam recorded hits like "Morning Has Broken" and "Moonshadow" before his conversion in 1977 impelled him increasingly away from music and toward religious and political pursuits. He is the director of an Islamic primary school in London. He raised funds for children victimized in Bosnia and is a vocal opponent of the war in Iraq.
Israel barred his entry in 2000, claiming he donated funds to Hamas, the militant Palestinian group, during a 1988 visit. Islam protested that he had donated funds to a home for invalids and to a hospital.
"At no time did I know consciously that I'm giving to a group called Hamas," he said at the time.
Straw was said to have registered Britain's concern about the underlying judgment that led U.S. officials to single out a moderate Muslim leader like Islam.
Other officials indicated that they considered the U.S. action an overreaction that would infuriate moderate Muslims in Britain and elsewhere.
"The whole thing is totally ridiculous," Islam told reporters upon his arrival back in England, which was televised. "Half of me wants to smile," he said, "half of me wants to growl."
Asked if he felt victimized, he replied, "Absolutely, but you know, for God's sake, people make mistakes. I just hope they have made a big mistake."
One official in London wondered why U.S. officials did not act on the intelligence information it said it had by arresting Islam, or share it with British authorities if they regarded Islam as a potential threat.
Arriving at Heathrow Airport on Thursday morning, Islam said he intended to consult with legal counsel to seek an explanation.
The deputy secretary general of the Muslim Council of Britain, Abdul Bari, issued a statement saying, "Yusuf Islam is a deeply respected and very popular British Muslim figure, and his detention by the U.S. authorities is completely unacceptable." The council is an umbrella organization for more than 400 local mosques, schools and charities.
"The United States is shutting down its house, building walls around itself," another official of the organization, Anas Altikriti, told Reuters.
"It's crazy," Islam told reporters at the airport, according to news agencies, "everybody knows me from my charitable work, and now there has to be explanations, but I'm glad to be home."