Police sources told CBS2 the sergeant was inside his home Tuesday night when it appears he shot himself in the head.
First responders rushed to the scene in Hillcrest and took the sergeant to a nearby hospital, but the veteran policeman could not be saved.
Sources told CBS2 the sergeant's wife was home at the time of the apparent suicide.
The tragedy marks the 10th active-duty NYPD officer to take their own life this year. Including retired officers, it marks the 12th self-inflicted death in 2019.
WATCH: NYPD Commissioner Opens Up About Spike In Suicides
"It is a mental health crisis in the NYPD," he said. "We've had nine suicides so far this year. Prior to that, we average four to five per year for the last five years."
CBS2's Jessica Moore asked O'Neill what his personal message would be to an officer who is struggling.
"Take that step. Come forward. Confide in your partner. Confide in a friend. Confide in your family. Get help," he said.
The NYPD has listed the following resources for officers in need of help.
- Employee Assistance Unit: 646-610-6730
- Chaplains Unit: 212-473-2363
- POPPA (independent from the NYPD): 888-267-7267
- NYC WELL: Text, call, & chat www.nyc.gov/nycwell
- Lifeline: 800-273-TALK (8255)
- Crisis Text Line: Law enforcement officers can text BLUE to 741741 (non-law enforcement can text TALK to 741741)
- Call 911 for emergencies
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