The accident happened at around 9 p.m. Saturday, June 29, in Brentwood at a residence on Eastern Avenue near Nostrand Avenue.
Suffolk County Police said a 66-year-old man was in the yard when a firework exploded, severing his left hand and three fingers on his right hand.
He was taken to Stony Brook University Hospital in serious condition.
Investigators are asking anyone with information on the incident to contact Suffolk County Police at 631-854-8352.
Fireworks, including bottle rockets and Roman candles, are illegal across New York State. However, sparklers are legal in most jurisdictions.
You can find more information on the New York State Division of Homeland Security and Emergency Services website.
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