Tenn. shooting suspect followed al-Qaida leader: reports

Investigators exploring Chattanooga rampage gunman Muhammed Abdulazeez's Internet search history have discovered evidence that he followed a radical American al Qaeda militant, according to numerous reports.

Both ABC News and The New York Times reported late Monday that Abdulazeez followed Anwar al-Awlaki, an American al Qaeda leader who has been linked to earlier attacks on U.S. soil -- including the Fort Hood shooter and so-called Christmas "underwear bomber." Al-Awlaki remained a prominent figure even after he died in a drone strike in 2011, thanks to videos he was featured in.

See photos from last week's attack:

The news comes as Abdulazeez's family is trying to shed light on his personal struggles with mental illness, drug and alcohol addiction, factors they believe may have contributed to last week's fatal attack on two military sites that has rocked Chattanooga, Tennessee.

Through a spokesperson, Abdulazeez's family members have revealed he suffered from depression and possibly bipolar disorder. His parents said their son's mental illness caused him to turn to drugs and alcohol. Eventually he was caught in a downward spiral of substance abuse.

Another focus of the FBI's investigation are his travels before the attack. Abdulazeez spent seven months in Jordan last year. His parents have said they sent him there to "get away from bad influences in U.S."

Investigators are looking into who he was in contact with while in Jordan. A report emerged late Monday that he had visited Qatar as well, but officials from that country responded Tuesday saying he only flew through the country.

Intelligence officials tell The New York Times that there was no evidence yet of Abdulazeez making contact with the Islamic State or other extremist groups in the region. They caution that testing of his computer and phone are ongoing, and could reveal crucial evidence.

"The person who committed this horrible crime was not the son we knew and loved. For many years, our son suffered from depression. It grieves us beyond belief to know that his pain found its expression in this heinous act of violence," his family said in a statement.

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