Sandy Hook Elementary School Shooting: Shooter Allegedly 'Obsessed' with Mass Murderers

The crazed gunman responsible for the Sandy Hook Elementary School massacre was allegedly "obsessed" with mass murderers.

An undisclosed source close to the investigation of the Dec. 14 Newton, Conn., school shooting says the 20-year-old gunman Adam Lanza was trying to surpass Anders Behring Breivik's death toll of 77 people during the July 2011 massacre in Norway, CBS Evening News reports.

The source said Lanza considered himself in competition with Breivik, who detonated a bomb in Oslo killing eight and then shooting 69 people on a nearby island. The source added that Lanza picked the school because it was an easy target and had the "largest cluster of people."

Lt. Paul Vance, spokesman for the Connecticut State Police called the CBS report speculation, CNN reports.

"It's inaccurate ... I talked with CBS and told them that," he said, adding "We are dealing with a deceased shooter and trying to rebuild history."

But Vance did not dismiss the idea that investigators are looking into connections with the Norway massacre.

"We'll look at everything," Vance said. "One thing leads to another."

Breivik was convicted of voluntary homicide and committing acts of terror, he was sentenced fo 21-years in jail. Breivik was taken into custody by an elite Norway police unit after he blew up a bomb outside the prime minister's office in Oslo on July 22, 2011. Breivik than took a ferry to Utoya Island and mercilessly shot 69 people, many of whom were attending a youth camp.

Breivik, a ultranationalist, said he committed the massacre to fight multiculturalism in Norway.