New York City police detectives searched a studio apartment in Las Vegas that belonged to the suspected gunman in Monday's mass shooting at a Midtown Manhattan.

When I look into you and dad’s eyes, all I see is disappointment,” Tamura wrote to his mother in the note. “I love you, Momma. I’m sorry.”

A gunman who killed four people at a Manhattan office building bought the rifle from his supervisor at a Las Vegas casino, authorities said.