The incident happened around 9 p.m. Friday, March 22 in Bay Shore.
Suffolk County Police officers responded to a 911 call stating that a teenage man was shot at 1320 Ackerson Blvd.
When they arrived, they found Sean Mills, age 19, and a 17-year-old girl shot during an outside party with approximately 50 people in attendance.
Mills, of Bay Shore, was transported to a local hospital where he was pronounced dead.
The girl was rushed to a local hospital where she is being treated for non-life-threatening injuries.
The investigation is continuing.
Anyone with information is asked to call the Homicide Squad at 631-852-6392 or Suffolk County Crime Stoppers at 1-800-220-TIPS.
This is a developing story. Check back to Daily Voice for updates.
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