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.”

The deadly Park Avenue shooting happened at one of the the most exclusive addresses in Midtown Manhattan — the “Blackstone Building," which is home to financial giant Blackstone, the NFL and accounting firm KPMG among a slew of other corporate names.

The gunman in the Manhattan office shooting has been tentatively identified as a 27-year-old Shane Tamura from Las Vegas, as per reports. He is believed to have died from a self-inflicted gunshot wound.