AUSTIN -- A roommate of the Austin bomber is now being considered a person of interest, Rep. Michael McCaul said to Fox News.

McCaul, the chairman of the House Committee on Homeland Security, said Monday on "America's Newsroom" that one of Mark Conditt's two Pflugerville roommates is still being questioned in the case and is being considered a person of interest. McCaul said officials are trying to determine if he knew anything about the seven explosive devices Conditt discussed in a confessional taping.

From March 2 to March 21, six of the bombs exploded, killing three people and injuring others. The final device that detonated killed Conditt himself, medical examiners declared Monday.

On March 21, officials worked to clear Conditt's home where numerous explosive materials were discovered in primarily one room. Conditt's two roommates were detained and questioned. One of them was released on March 21, the second on March 22.

McCaul did not say what caused the roommate to be declared a person of interest after he was released.

As of Monday afternoon, officials have not identified either roommate.

McCaul's office released the following statement Monday evening:

"Law enforcement is combing through the serial bomber's cell phone and computer devices that could potentially lead us to a motive. Authorities are also questioning one of the roommates on whether he had any knowledge or involvement in making any of the explosive devices at home. Any person with knowledge of such a horrific act would have a duty to report it to the authorities and if they failed to do so could be complicit to the conspiracy."

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