HARTFORD, Conn. (CBSNewYork/AP) — Connecticut’s chief medical examiner said he’s seeking genetic clues to help explain why a shooter killed 20 children and six adults in a Newtown elementary school.

Dr. H. Wayne Carver told The Hartford Courant that he wants to know if there is any identifiable disease associated with the behavior of the gunman, Adam Lanza. He is working with the University of Connecticut department of genetics.

“I’m exploring with the department of genetics what might be possible, if anything is possible,” Carver said.

Lanza’s motive behind Friday’s mass shooting remains a mystery.

Authorities said the horrific events began when Lanza shot his mother, Nancy, at their home, and then took her car and some of her guns to Sandy Hook Elementary School.

There, he forced his way into the building and opened fire, killing 20 children and six adults before shooting himself.

Investigators have found no letters or diaries that could explain the attack. Computers found in the Lanza home had been smashed. The FBI was trying to recover documents from the hard drives.

Those who knew Lanza described him as a bright, but awkward young man. He took college classes when he was only 16, a spokesman for Western Connecticut State University said Monday.

Paula Levy, a mediator who worked with Lanza’s parents during their divorce, has said Lanza was diagnosed with Asperger’s syndrome, an autism-like disorder.

Carver says Asperger’s is not associated with violent behavior. He says he’s not considering it as a reason for Lanza’s rampage on Friday.

Carver is awaiting toxicology testing results for Lanza and other information.

(TM and Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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