A 15-year-old boy was stabbed multiple times by another teenager Saturday at the Holbrook Chamber of Commerce Fair, police say.

Chrystie Cottone, of East Islip, says her 13-year-old son was initially beaten up by a 16-year-old boy while he was waiting on line for a ride.

She says when she and her family were leaving the festival, they were confronted by the same 16-year-old, who her son identified as the one assaulting his brother.

Cottone says her 15-year-old son was then stabbed by the teenager.

“In a matter of 10 seconds I heard my husband screaming to my oldest, who is 15, to move back, he had a knife,” Cottone says. “I heard my sister-in-law scream and then I heard my son scream that, ‘I’ve been stabbed.’

The 15-year-old was rushed to the hospital with stab wounds in his shoulder, back and stomach. He had a four-hour surgery.

Cottone says she and her family are left with the physical and emotional scars from the terrifying incident.

The 16-year-old was arrested and charged with assault and criminal possession of a weapon. He was arraigned and sent home.

Members of the Holbrook Chamber of Commerce sent News 12 a statement, saying, “The Holbrook Chamber was very pleased with the Suffolk County Police Department and Holbrook Fire Department EMS’ responses as bother were on site at the time of this very unfortunate event.”