Police in Arizona have arrested a former US navy sailor on charges of spying and providing material support to terrorists.
The US Attorney's office in Connecticut said Hassan Abujihaad, formerly known as Paul Hall (31), was arrested in Phoenix.
He is suspected of providing classified information to a London-based organisation called Azzam Publications and knowing that it was to be used in preparation for, or in carrying out, a conspiracy to kill US citizens.
The charges related to disclosure of the movement of a US Navy battle group as it travelled from California to the Gulf in 2001, prosecutors said.
The charges were brought in Connecticut because the Azzam Publications websites were hosted for a time on servers in the state.
The complaint alleged that Mr Abujihaad sent several e-mails to members of Azzam Publications while he was on active duty in the Middle East and stationed aboard the USS Benfold,one of the ships in the battle group whose movements were disclosed.
The e-mails were recovered after a search in December 2003 by British police of the London home of Babar Ahmad, a British national linked to the organisation.
Mr Abujihaad was discharged from active duty from the United States Navy in January 2002.