FortHood, Texas - US Federal investigators probing the Fort Hood shooting were on Monday studying the gunman's relationship with an imam who has been linked to the al-Qaeda terrorist group, according to a newspaper report. Army psychiatrist Major Nidal Malik Hasan shot and killed 12 soldiers and one civilian at the Texas army base last Thursday. At least 30 additional people were wounded in the attack.
The Washington Post reported that federal investigators were probing possible links between Hasan and Anwar al-Aulaqi, an American-born imam who had contact with two of the hijackers in the terrorist attacks on the US on September 11, 2001.
Though they still believe Hasan acted alone and without direct involvement from al-Aulaqi, who left the US for Yemen in 2002, investigators are examining Hasan's computer files for possible connections to the imam, the paper reported.
Hasan attended Dar al-Hijrah mosque in Falls Church, Virginia, in 2001, when al-Aulaqi led the congregation there.
US Senator Joseph Lieberman has called for a congressional investigation into whether the shootings were motivated by terrorism. He told Fox News there had been "strong warning signs" Hasan was an "Islamist extremist".
President Barack Obama, who has been criticized for not acting more swiftly and empathetically to the tragedy, is scheduled to attend a memorial service at the base on Tuesday.
Investigators have already conducted more than 170 interviews, but have not yet found any evidence of accomplices to the crime or clear links to a terrorist motive.
Hasan, who remained in the intensive care unit of an Army medical centre in San Antonio on Monday, has been taken off a ventilator. He was said to be conscious and talking.
