A former US navy sailor has been convicted of spying and supplying a pro-al-Qaeda website with information on American warship movements.
Abujihaad was convicted of providing support to terrorists
Hassan Abujihaad, 32, was found guilty of providing material support to terrorists and disclosing secret national defence information.
He was arrested last year in Phoenix, Arizona.
Abujihaad, a Muslim convert previously known as Paul Hall, faces 25 years in jail when he is sentenced on 23 May.
He showed no emotion as he was convicted of passing classified details of US navy ships to Azzam.com by a jury at the US District Court in New Haven, Connecticut.
Azzam was an Islamist website that prosecutors said had actively supported terrorists but has now closed.
Abujihaad had served as a naval signalman on board the USS Benfold while it was part of a battle group in the Middle East engaged in anti-Taleban and anti-al-Qaeda activities.
He used his security clearance to e-mail Azzam diagrams of ships and their susceptibility to attack, as well as details of the US Navy battle group and its planned movements through the Straits of Hormuz in April 2001.
The spying took place just months after a suicide attack on the USS Cole in Yemen in October 2000, killing 17 sailors.
"According to navy officials, knowledge of ships' movements, missions and capabilities would be extremely useful in planning a successful terrorist strike," said an FBI affidavit.
Abujihaad knew the information he supplied would be used to attack Americans, the US justice department said.
An investigation began in 2003 when police in Britain arrested the Babar Ahmad, a computer specialist working on Azzam, and found a computer disk in his home containing the classified US navy information.
Mr Ahmad is currently being held at Woodhill Prison in the UK, where he is fighting deportation to the US on charges of raising funds for terror groups.
US-born Abujihaad had been honourably discharged from the navy in 2002. His lawyers said they were likely to appeal the conviction.