The Midtown Manhattan office shooter fired 47 rounds from his M4-style rifle during the rampage, a number that indicates the suspect, Shane Tamura, reloaded his rifle at least once, the NYPD said. There were 23 shell casings and 13 bullet fragments recovered from the lobby of 345 Park Avenue, police said.

The 27-year-old man who shot and killed four people at a Midtown office building on Monday carried a note in his pocket claiming he suffered from CTE, asked that his brain be studied and made references to the NFL.