A decade before police say he gunned down four people at a Manhattan tower that is home to the National Football League, Shane Tamura was a celebrated high school football star whose coach once described him as “lightning in a bottle” and among the most talented athletes he’d ever seen.
Now, investigators are looking into claims in Tamura’s suicide note that link the deadly attack to his years playing football.
The 27-year-old Tamura walked into the office building Monday evening carrying an assault rifle — and a suicide note in his back pocket alleging that he suffered from CTE, a brain disease linked to head trauma, according to a source with knowledge of the investigation.
After killing four others, including an off-duty New York police officer, Tamura fatally shot himself in the chest, police said. In the note, according to the source, Tamura expressed grievances with the NFL and asked for his brain to be studied.
Police said Tamura’s motives are still under investigation, and he had “a documented mental health history.” The short note was scribbled over three pages and found by investigators after the shooting, the source said.
“Terry Long football gave me CTE and it caused me to drink a gallon of antifreeze,” the shooter wrote, according to the source, referring to Terry Long, a former NFL player who was diagnosed with CTE and died by suicide after drinking antifreeze in 2005.
The note continued, “You can’t go against the NFL, they’ll squash you.”
Tamura, who most recently lived in Las Vegas, spent his high school years in the Los Angeles area, where he played several seasons as a running back for Golden Valley High School in the suburb of Santa Clarita.
His athletic accomplishments were chronicled in the Santa Clarita Valley Signal newspaper. A 2013 article described Tamura as the Golden Valley Grizzlies junior varsity team’s “biggest weapon” on offense and noted his coach believed he was the most athletically gifted player. The Golden Valley head coach, Dan Kelley, referred to him as “lightning in a bottle” in an interview for a 2014 article.
Tamura accounted for more than half of the team’s touchdowns over roughly the first month of the 2014 season, and was a big reason for their overall success, the newspaper reported.
“He’s a game-breaker. You definitely want the ball in his hands,” Kelley said. “He’s even harder on himself when he doesn’t take it all the way. I always have to remind him that not every play is going to go for a touchdown.”
Tamura once doubted he would make the starting lineup, he told the newspaper.
“Going from JV to varsity is a huge difference and it’s surreal to be seeing the ball this much and having the team doing so well,” he said. “It’s great being a big part of everything and scoring a lot of touchdowns, but I have to keep getting better… I need to keep pushing myself.”
His older brother Terry also played football, according to friends and local coverage. When asked about his brother’s skills in 2014, Terry said, “We’re similar… He’s a little quicker though and probably more elusive, too.”
Coach Kelley did not hold back in his praise of the younger Tamura. “This is my 20th year coaching high school football and he’s one of the most talented kids I’ve seen,” he said. “The sky is the limit with Shane, if he dedicates himself to the weight room and becoming the best football player in this valley, I think he has the capability.”
A former teammate, who asked not to be named, told CNN he remembered Tamura as “being well-liked, having friends from different groups in school,” and going biking and swimming together with friends.
“He ran really hard and he really cared about his team,” said the teammate, who said he didn’t remember Tamura disclosing any head injuries.
Tamura transferred to Granada Hills Charter School in nearby San Fernando Valley in 2015 for his senior year of high school, where he played for the Highlanders football team.
Walter Roby, who coached the team, told CNN that Tamura was “by far my best running back at the time.”
“He was warm, soft-spoken, hard-working,” Roby said. “He did what you asked him to do and he led by his example… He would come up, smile, hug, warm embrace.”
Roby said he never saw any signs of violence or other trouble from Tamura and had no memory of him suffering a head injury.
In a video posted to YouTube in 2015 after his team won a game, Tamura answered questions from an interviewer who called him a “standout running back.”
“We just had to stay disciplined and come together as a team,” Tamura said. “Keep playing, keep fighting through it, and just hold our heads up high, and a good result’s going to come.”
Another friend and former teammate also told CNN that Tamura never mentioned a head injury or any kind of mental illness.
“We were kids back then, so mental illness — we don’t really pay much (attention) to that topic,” the teammate said.
He said Tamura was one of his closest friends, but they lost touch after high school. Tamura reached out to him a few months ago on Instagram just to say hello, but before that, they hadn’t spoken in more than 10 years.
It’s not clear whether Tamura played football after his high school years or if he was ever diagnosed with any brain injuries connected to his athletic career. CTE, which has been associated with head impacts suffered by some football players, is generally only confirmed after death.
Tamura’s death echoes at least one previous high-profile CTE case: Former NFL player Dave Duerson also shot himself in the chest and left a note asking for his brain to be studied.
The NFL has acknowledged a link between football and brain disorders like CTE, and has said in recent years that it has made changes to eliminate some unnecessary contact to the head and neck areas during practice and games.
Tamura worked as a “surveillance department employee” at Horseshoe Las Vegas, a hotel and casino, a spokesperson said in a statement Tuesday. He received private investigator licenses in California and Nevada in 2019, both of which later expired, according to public records.
Court records show that Tamura was charged with misdemeanor trespassing in 2023 in Clark County, Nevada. According to a police incident report, Tamura refused to leave a Las Vegas casino after attempting to cash out about $5,000, and security called police, who handcuffed and arrested him. A court database suggests a district attorney declined to pursue the case.
Police said Tamura drove his BMW across the country from Las Vegas over the last few days, and that he double parked it in front of the Park Avenue office building before walking in with a rifle.
He opened fire in the lobby, killing off-duty NYPD officer Didarul Islam, who was working as a security guard, and then took an elevator to the 33rd floor. Tamura gunned down several other people at a real estate office before fatally shooting himself in the chest.
The NFL’s headquarters are on the building’s fifth floor, but Tamura “mistakenly went up the wrong elevator bank,” Mayor Eric Adams told a local news station.
