(NEW YORK) -- The official spokesman for the Connecticut State Police, the lead agency investigating the mass shooting in Newtown that killed 26 students and teachers at Sandy Hook Elementary School, cast doubt Tuesday on reports that shooter Adam Lanza was trying to emulate Norwegian killer Anders Breivik or other mass murderers.
"It's someone's theory, but not ours," Lt. Paul Vance told ABC News. "It's not anything official that we've garnered."
On Monday, CBS News reported that two officials briefed on the Newtown investigation said Lanza saw himself "as being in direct competition" with Breivik. In July 2011, Breivik killed eight people with a bomb in Oslo, then went to a nearby resort island crowded with teenagers attending a summer camp and shot and killed 69 more people.
The CBS report also said the sources think Lanza wanted to "top" Breivik's death toll and may have been acting out a scenario from a video game, complete with a "score."
"I can't substantiate that at all and, quite frankly, that did not come from us," said Vance. "It's nothing that came from us and we are the official agency investigating."
The Hartford Courant reported that investigators had found several news articles about Breivik in one of Lanza's two bedrooms, citing two law enforcement sources familiar with the investigation, but Vance said they "never, ever detail evidence we see at a crime scene."
James Fox, a professor of criminology at Northeastern University and a mass shooting expert, said in these types of cases "it is common for some mass murderers to emulate others and to try and outdo them and even try to break a record."
"That's why it's a problem to be constantly talking about [killings] being a record because records are there to be broken," Fox said.
Media outlets have also reported that investigators recovered a large number of video games from the basement of the Lanza home, and that he spent many hours there alone working on his computer shooting skills. Before his shooting spree, Lanza tried to destroy his computer hard drive, making it more difficult to trace his activities.
Richard Novia, who advised the tech club to which Lanza belonged at Newtown High School, said Lanza's taste for video games didn't set him apart from his peers.
"It wasn't just Adam Lanza, all the kids were playing them," said Novia. He said he didn't know about Lanza's home life, but didn't think he played games more than the other Newtown kids at the time.
"He was definitely a kid who liked computers, who liked to play games when he was younger. He was a recluse type," said Novia. "It makes sense with his personality and his lifestyle that that's what he would be doing." Lanza left Newtown High School at age 16.
James Fox said Lanza's obsession with video games was more likely "a symptom than a cause."
"The issue is being reclusive, and his reclusiveness was related to his immersion into video games and related to his issues of awkwardness and anxiety and isolation, which led to the murders," he explained.
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