Investigators believe Tamura was trying to get to the NFL offices but mistakenly entered the wrong elevator. Now, on the other side of the country in Los Angeles, we're seeing more security outside of the NFL's West Coast Headquarters.
Inglewood Mayor James T. Butts Jr. told Eyewitness News the increased police presence at the NFL West Coast Headquarters is just a precaution. He says the NFL reached out to the city asking for additional security and added that the NFL is reimbursing the city for the cost.
"We're making a statement that, although we don't feel that there's any conspiracy or connectivity on this coast to what happened in New York, that we want the public and the NFL to know that we're there for them," Butts said.
With more than a thousand employees, the NFL's West Coast Headquarters serves as the hub for NFL media operations, studios and offices.
Butts, who has 37 years of law enforcement experience, says there's no evidence of a threat in Inglewood. The increased police presence is meant to help employees at the NFL West Coast Headquarters feel secure and send a message.
"Anytime you have an incident that gets national, international attention and publicity, you want to make a counter statement that, while we don't feel that we're at risk, that we're not taking any chances and that we're going to have extra security for them," Butts said.
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As a teen, Tamura played football in Santa Clarita and later at Granada Hills Charter School.
Tamura's father was a Los Angeles Police Department officer who served for 27 years and retired in 2017, the agency said.
Police investigating the deadly Midtown shooting found two notes from the gunman, sources told ABC News.
One page of the first note found in Tamura's pocket accused the NFL of concealing the dangers to players' brains from playing football in order to maximize profits, sources said.
A second page mentioned CTE and blamed football. A third page asked, "Study my brain please. I'm sorry," sources said.
CTE, or chronic traumatic encephalopathy, is a brain disease linked to repeated hits to the head, often seen in military veterans and athletes, including football players, hockey players and boxers.
Tamura has no known connection to the NFL. It remains unknown if Tamura suffered from CTE, which can't be diagnosed in a living person with certainty, but doctors may suspect it based on symptoms and a history of head trauma. Tamura's brain will be examined as part of his autopsy, the New York City Office of the Chief Medical Examiner said.
During a press conference on Monday evening, NYPD Commissioner Jessica Tisch said Tamura had a "documented mental health history."
NFL commissioner Roger Goodell released a statement on Tuesday, saying:
"I want to take a moment to reach out to you all following yesterday's tragic events. Our hearts go out to all of the victims and their families, and we are deeply grateful for the first responders and medical staff who acted so quickly and continue to provide care.
Our thoughts and prayers remain especially with our colleague who was impacted. He is currently surrounded by his family and members of the NFL community, and we are all continuing to hope for and support his full recovery.
For those of you based in our New York office, please plan to work remotely at least through the end of next week (August 8). The office will remain closed during this time, and we ask that you do not attempt to enter the building until we confirm that it is ready for us to return.
We are strongest when we come together and support one another. To provide a space for our community, we will be holding a virtual town hall tomorrow where we can connect, share, and support each other. More details to follow.
This has been a challenging time for our entire team. Please continue to take care of yourselves and one another. If you need additional support, do not hesitate to reach out to your manager or HR. We are here for you.
Thank you to all of you for the compassion, care, and support you are showing to one another right now. It means so much to see how our team is pulling together.
In the midst of this difficult time, we hold on to hope and optimism for healing and brighter days ahead."