The New York City Police Department sent detectives to Las Vegas to work with the Bureau of Alcohol, Tobacco and Firearms to execute search warrants and continue the investigation into Monday’s deadly shooting inside a Midtown Manhattan office building.

According to an NYPD spokesperson, the goal is to build a timeline on 27-year-old gunman Shane Tamura’s motives and mental health leading up to the attack at 345 Park Ave., which killed four people, including an NYPD officer.

Investigators hope to gather information through a series of eyewitness interviews, as well as searches for phones and computers, to build a more comprehensive picture of where, why and what the gunman did leading up to him driving from Las Vegas to New York City.

More ammo, another note found in gunman’s Vegas apartment

As of Tuesday, a search warrant was served at the gunman’s studio apartment in Las Vegas, where NYPD investigators found a tripod for a rifle, 100 9mm live rounds, as well as another suicide note that reads, “When I look into you and Dad’s eyes, all I see is disappointment. I love you Momma, I’m sorry.”

Also inside the apartment, investigators found one prescription for anti-psychotic medications with the gunman’s name, one anti-inflammatory prescription, and one anti-epileptic prescription.

Police were still waiting Wednesday for search warrants for a computer, a phone and the suspect’s locker at the Horseshoe Casino,  where he worked.

According to the NYPD, the gunman’s two phones, which were found at the crime scene in Manhattan, were searched and show two incoming calls as he traveled from Las Vegas to New York City. One was received on Sunday from a cell tower in Geneseo, Illinois, and the other was received on Monday from a cell tower in Parsippany, New Jersey.

Police are going to speak to both of those callers to see what the substance of the calls were and whether they knew of the shooter’s intentions.

Investigators also plan to speak with the gunman’s parents at their home, police said. The gunman’s father is a former officer, a Los Angeles Police Department spokesperson said, adding, he retired in good standing in 2017.

Gunman associate “Rick” cooperating with police

Investigators also spoke to a person named “Rick,” the gunman’s supervisor at the Horseshoe Casino, and he is said to be “cooperative,” according to police. He said he purchased a fully assembled AR-style rifle in Las Vegas and sold that rifle, the one used in the New York City office shooting, to Tamura for $1,400.

Rick’s purchase of the rifle was legal, but police have not been able to confirm if his sale to the suspect was legal, a spokesperson said, adding it will be up to the Las Vegas Police Department to determine. 

Rick has not been arrested or charged with a crime at this point.

Rick also sold the gunman the black BMW he used to travel cross-country to New York City, before leaving it double parked at the scene of the shooting, police said.

Questions about gunman’s concealed carry permit

Back in New York City, there is growing outrage as officials are partly blaming the tragedy on looser gun laws in other states.

State Assemblyman Charles Lavine sent a letter to Nevada’s governor, asking, “How someone with a history of mental problems was able to procure a concealed firearms permit…”

Tamura had a Concealed Carry Firearms Permit. After it was issued, sources say, he was involved in two separate mental health incidents, including one where he allegedly told police he was suicidal.

Despite that, and a 2023 trespass arrest, his permit stayed valid.

Phil Ramos, a former senior homicide detective in Las Vegas, told CBS News New York’s Mahsa Saeidi, “It gets you the ability to go get a weapon without the usual background check. So a citizen who’s not had a CCW or a background check and goes in and wants to buy a handgun, he’s not gonna get it an hour later. You gotta come back after you’ve been checked.”

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