Police believe the AWOL American soldier accused of planning a bombing and shooting spree outside Fort Hood, Texas was inspired by al Qaeda.
Officials told ABC News that Pfc. Naser Jason Abdo hid an article from the first issue of al Qaeda's Inspire magazine called "How to Build a Bomb in the Kitchen of Your Mom."
FBI spokesman Erik Vasys said agents found potential bomb-making materials in the soldier's hotel room.
Abdo, 21, was arrested on Wednesday. He had refused to deploy to Afghanistan and later went AWOL from Fort Campbell in Kentucky, after he was charged with possession of child pornography, Vasys told CNN.
It was a tip from a local gun shop that led Killeen police to arrest Abdo at a traffic stop, officials said. He is being held in Killeen City jail.
"He's a very dangerous individual and he is where he needs to be," Killeen Police Chief Dennis Baldwin told CNN.
ABC News reported that an official said Abdo mentioned the name of American-born Anwar al-Awlaki, one of the most high-profile leaders in the Yemen-based al Qaeda.
CNN reported that Abdo, who is expected to face federal charges, told investigators he wanted to attack his soldier colleagues at the military post.
"Military personnel were a target of this suspect," Baldwin said.
The military base was the scene of a shooting rampage in 2009. Muslim American Maj. Nidal Hasan, an Army psychiatrist, is accused of killing 13 people and wounding more than 30 others in an attack on the base.