Live updates: Midtown Manhattan NYC shooting, Shane Tamura killed 4 people including NYPD officer

Police found a host of items in the car of the gunman who killed four people in Manhattan on Monday, according to a law enforcement source, including ammunition and another loaded weapon.

The items included a box containing plastic bags of ammunition and an additional loaded magazine for the rifle investigators say the shooter used in the attack, according to the source and photos obtained by CNN. The suspect also had headphones, likely used for ear protection or target practice, the source said.

Shortly before 6:30 p.m. Monday night, surveillance cameras captured the gunman leaving the car near the Park Avenue building and entering with an M4 assault-style rifle in hand, New York City Police Commissioner Jessica Tisch said.

Police found a loaded revolver and rifle case in the vehicle, Tisch said. The car was left at the scene, police said.

Authorities also recovered two cell phones, Zoloft – an antidepressant – and cannabis, the source told CNN.

The suspect’s note: A handwritten note found on the gunman contained a list of names of neuroscientists. There were no further notes next to the names. CNN has viewed a copy of the note.

The note, which was found in his pocket, stated he suffered from CTE, or chronic traumatic encephalopathy, a brain disease linked to head trauma, a source with knowledge of the investigation said.