Overview

• The New York City medical examiner found unambiguous evidence of low-stage chronic traumatic encephalopathy in Shane Tamura’s brain and did not determine the disease’s cause.
• Authorities say Tamura traveled from Nevada, held a valid Las Vegas concealed-carry permit, and used a legally purchased M4-style rifle.
• A three-page note recovered from Tamura blamed the NFL for concealing brain-injury risks and asked doctors to study his brain.
• On July 28, he entered 345 Park Avenue wearing body armor and killed four people, including NYPD Officer Didarul Islam, before dying by suicide.
• Victims include two corporate employees—one a Blackstone executive—and an NFL-affiliated staffer remains hospitalized in critical condition, as investigators continue retracing Tamura’s movements.