Suspect's Movements Suggest Al Qaeda Ties

ABC News has learned of strong new connections between an alleged terrorist plot to blow up planes over the United States and al Qaeda training grounds.

Rashid Rauf, the alleged al Qaeda operative thought to be the ringleader of the busted plot, was traced by British intelligence to Pakistan last month.

He was picked up near the Afghan border, in an area where al Qaeda training camps are thought to operate. Information he gave to Pakistani intelligence led to the raids and arrests in England.

Tonight, 23 suspects are in custody in London. They were all arrested in quiet, suburban neighborhoods. All of them were born in Britain.

But what could turn someone like 26-year-old Assad Sarwar, a suspect depicted in one of two photos published by Britain's Daily Mail newspaper, into an alleged terrorist?

London has long been considered a hotbed of Islamic fundamentalism. Authorities say fiery clerics have exploited a breeding ground for extremists among Britain's 1.6 million Muslims.

British security officials believe that terrorist recruiters target mosques and Muslim community centers looking for potential bombers.

"Slowly, over a period of time, they cultivate them, indoctrinate them," said Sajjan Gohel of the Asia-Pacific Foundation. "[They] encourage them to go abroad to countries like Pakistan, which has become known as a finishing school for extremism."

Today, moderate Muslim leaders sent an open letter to Prime Minister Tony Blair arguing that British foreign policy has spread anger throughout the Muslim community.

"The debacle of Iraq," they wrote, "is … ammunition to extremists who threaten us all."

Three of the July 7 suicide bombers last year were British-born Muslims and two of them recorded so-called martyrdom tapes.

"You are directly responsible for the problems in Palestine and Afghanistan and Iraq to this day," one of the bombers said in his tape.

"We are at war and I am a soldier," said another.