A 73-year-old woman was injured Thursday morning after inadvertently setting off a firework.

Police say the woman, a Florida resident, was cleaning up after a July Fourth party at her son’s home on Carlton Avenue.

They say she placed a lit cigarette in an ash tray, which caused a firework in the ashtray to explode.

Authorities say the explosion severed the tip off of her finger and injured other fingers on her right hand.

The woman, who was alone at the house at the time of the incident was taken by police helicopter to Stony Brook University Hospital.