Boy, 15, fatally stabs grandmother, injures mother in Selden home, authorities say

A 15-year-old Selden boy fatally stabbed his grandmother while his mother, who was also stabbed, played dead on the kitchen floor, following a dispute over the boy skipping school and barricading himself in his room on a computer, a prosecutor said Tuesday.

The boy, whom Newsday is not naming because he is a minor, pleaded not guilty to second-degree murder and attempted murder charges in Suffolk County District Court in Central Islip.

Judge Karen Kerr ordered the boy held without bail.

The boy's defense attorney, Pete Mayer, said after court that the boy is a "child" and, like all defendants, has the presumption of innocence. He declined to comment further.

Assistant District Attorney Dena Rizopoulos said police received a 911 call at 9:49 p.m. Monday reporting the stabbing.

"The defendant has been acting out as of late, skipping school, barricading himself in his bedroom on his computer," Rizopoulos said.

His mother, identified by police as Vanessa Chendemi, 35, threatened to take his computer away, Rizopoulos said, prompting the boy's grandmother to say: "just take the computer."

At that point, the attack began.

"The defendant's mother fell to the kitchen floor and pretended to be dead to stop the attack," Rizopoulos said.

The boy's mother could hear her mother "pleading for help," Rizopoulos said.

The boy's mother fled the home and flagged down a passing motorist who called 911, she said.

The boy also fled the home on foot and was arrested at 10:35 p.m. with the assistance of a police K-9, the prosecutor said.

His hands were covered in what appeared to be blood and police found two knives with what appeared to be blood on them near the boy, the prosecutor said.

Police also saw blood throughout the house and found part of a knife that appeared to be broken off in the house, the prosecutor said.

When officers arrived, they found Concetta Chendemi, 56, inside the residence with stab wounds, police said.

She was pronounced dead at the scene by a physician assistant from the Office of the Suffolk Medical Examiner, according to police, and Vanessa Chendemi was taken to a hospital.

Suffolk Det. Lt. Kevin Beyrer said that Vanessa Chendemi called police from her Old Town Road home to report that she and her mother had been stabbed by her son, who had run from the house.

A passing motorist stopped and offered her assistance and also called 911, Beyrer said.

Beyrer said the family had argued about something they found on the 15-year-old’s computer before the incident.

Vanessa Chendemi was in serious condition at the hospital; she is expected to survive, said Beyrer, the commanding officer of the Suffolk police Homicide Bureau. She suffered stab wounds to the arms, back, neck and face, he said.

"She is obviously distraught," Beyrer said.

The prosecutor said the boy's mother is unable to see out of her left eye, as she has a severe laceration from her left eyebrow to the bridge of her nose.

Concetta Chendemi was stabbed in her chest, abdomen and leg, the prosecutor said.

A woman who said she is the boy's aunt cried out during his arraignment, saying "I'm here for him," when the prosecutor told the judge he should be remanded.

The judge told the woman she'd have to leave if she continued.

The woman declined to speak to reporters.

Old Town Road was blocked off by police tape at Orange Avenue midmorning Tuesday where a Suffolk Medical Examiner's truck and several police cars were parked outside the house.

Neighbor DJ Cortez, 29, said he was getting his son ready for bed Monday night when he heard police sirens.

"We just came outside and cops were everywhere. It was insane," Cortez said.

Cortez, who didn't know the family, said he has lived in the neighborhood for most of his life and is shocked by the tragedy.

"It's terrible," he said. "It's something you would never think to hear."