The Texas army camp massacre gunman was being investigated for possible links to an extremist website, it has emerged. Skip related content
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Fort Hood gunman 'suspected of extremism'
Military psychiatrist Major Nidal Malik Hasan is in hospital under armed guard after opening fire at a station used to ready soldiers for deployment overseas at Fort Hood.
Within minutes, at least 13 soldiers were dead or dying in the worst mass shooting ever at a US military base. At least 31 others, including two civilians, were injured in an attack described by President Barack Obama as a "horrific outburst of violence".
Hasan had come to the attention of law enforcement officials at least six months ago because of internet postings that compared suicide bombers to soldiers who throw themselves on a grenade to save their comrades' lives.
Investigators were not certain whether Hasan had written the posts and a formal investigation had not been opened before the shooting, law enforcement sources said.
But authorities have not ruled out that Hasan was acting on behalf of some unidentified radical group. Nor are they ruling out the possibility that some of the casualties were shot accidentally by military officials who responded at the scene.
Retired Colonel Terry Lee, who worked with Hasan, claimed the 39-year-old was anti-war and had rowed with comrades who supported operations in Iraq and Afghanistan. Hasan was due to be sent to Afghanistan, something his family described as his "worst nightmare".
Hasan was shot four times but survived and was being treated in hospital under armed guard.
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