A radical Muslim cleric detained in London early Thursday is charged by a US court with 11 terrorism-related crimes, including trying to set up a terror training camp in the United States and assisting in the kidnapping of Americans and others in Yemen.

The 11-count indictment unsealed in federal court in Manhattan was returned by a federal grand jury on April 19. US authorities are seeking to extradite al-Masri, who was arrested earlier Thursday in London.

"The United States will use every diplomatic, legal and administrative tool to pursue and prosecute those who facilitate terrorist activities," said US Attorney General John Ashcroft at a press conference in New York on Thursday. "And we will not stop until the war against terrorism is won."

If convicted of the most serious charge against him -- hostage taking -- the 47-year-old cleric could face the death penalty or life imprisonment.

The indictment charges al-Masri, whose real name is Mustafa Kamel Mustafa, with hostage taking in connection with an attack in Yemen in December 1998 that resulted in the death of four hostages.

It also accuses him of trying to establish a terrorist training camp in Bly in the northwestern state of Oregon between 1999 and early 2000.

Other charges against him include specifically providing material support to al Qaeda and the Taliban to foment "violent Jihad" in Afghanistan.

Al-Masri was formerly the imam at a mosque in London, which has been linked to several terrorist suspects, including Sept. 11 suspect Zacarias Moussaoui and "shoe bomber" Richard Reid.

In London, al-Masri's lawyer said his client was detained earlier in the day, and police sources indicated he was detained on an extradition warrant at the request of the US authorities.