Police have identified the man who entered a Midtown Manhattan office building wearing body armor and opened fire killing four people with a high-powered rifle, as Shane Devon Tamura.

The 27-year-old recently lived in Las Vegas, where he was issued a concealed firearms permit by the Las Vegas Police Department. He was previously issued a work card by the Nevada Private Investigators Licensing Board, which has since expired, according to records reviewed by ABC News. His last known address was in a gated community in Las Vegas.

Several squad cars from Las Vegas Metro Police have convened at entrances to a gated neighborhood where Tamura was believed to have lived.

He completed high school in the Los Angeles area, where he was a competitive football player, according to a school official who spoke with ABC News. Caleb Clarke, a former classmate of Tamura at Santa Clarita High School, described him as a “goofball” and did not recall him having any mental health issues. Tamura played as a running back with Grenada Hills Charter for a portion of his high school career.

New York Police Commissioner Jessica Tisch said Tamura had a “documented mental health history.” He recently drove from Las Vegas to New York, and officers found additional ammunition, a revolver, a backpack, and medication inside his vehicle.

The initial investigation shows his vehicle traveled through Colorado on July 26, then Nebraska and Iowa on July 27, and then in Columbia, New Jersey, as recently as 4:24 p.m. on Monday, with his vehicle entering New York City shortly thereafter, Tisch said.

After entering 345 Park Ave. and “spraying it with gunfire,” he took the elevator to the offices of real estate management firm Rudin Management on the 33rd floor, where he shot and killed one additional person. Tamura was found dead from what is believed to be a self-inflicted gunshot wound, officials said.

ABC News has reached out to Rudin Management for comment. Police have not identified why he went to that floor or if he has any connection to the company.

“His motives are still under investigation, and we are working to understand why he targeted this particular location,” Tisch said.