Two teams of detectives were sent to Las Vegas to execute a search warrant on the shooter's home and investigate the weapons used in the attack. Investigators discovered that parts of the automatic weapon had been purchased by someone else, raising questions about potential assistance in the crime.

NYPD detectives searched the shooter's studio apartment in Las Vegas where they found what law enforcement sources described to ABC News as a suicide note that said, "When I look into you and dad's eyes, all I see is disappointment. I love you, Mama. I'm sorry."

Shane Tamura, the shooter behind the deadly rampage in Midtown Manhattan,​ was apparently targeting NFL offices, NYC Mayor Eric Adams says.