aaron alexis*(Via CBS News)  – Investigators continue to piece together information about Navy Yard shooting suspect Aaron Alexis, who carried out an attack that left 12 dead and eight injured Monday.

CBS News special correspondent and former FBI assistant director John Miller reports there are no indications that the suspect was self-radicalized. Rather, it is likely he was a disgruntled worker with anger management issues. Miller also said that he had sought treatment for mental health issues from the Veteran’s Administration.

“The indications are [that] he was a government worker with a secret clearance who was a devout Buddhist,” Miller said on “CBS This Morning.”

“There were mental issues that he sought help for from the VA a number of times. He was … acting normally during work and then having these episodes for which he was trying to get treatment.”

“He said he was hearing voices, he was detached from reality at certain points. He had sought treatment a number of times at a number of places and he was also frustrated there. He claimed he wasn’t getting his full VA benefits,” Miller said.

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