Massachusetts teen accused of killing mother, brother with help from ChatGPT

A Massachusetts teenager used a laptop and knife to beat his mother and brother to death, hours after using ChatGPT to search “for theoretical ideas or fantasy stories regarding the killing of his family,” prosecutors said Thursday.

Arjun Aravind, 17, of the affluent Boston suburb of Acton, was charged with two counts of murder in the slayings of Sudha Venkatesan, 45, and Siddharth Aravind, 14, according to a criminal complaint filed in Concord.

He also faces assault and battery charges for allegedly using “a dangerous weapon, a Laptop” to attack his two victims, the complaint states.

Investigators said “a heavily damaged bloody laptop computer was found consistent with it being used during the assault,” according to the complaint.

Police also found what appeared to be a knife that was used in the attack.

“A bent utensil, possibly a knife with an orange handle, was also found in the area of the disturbance,” the complaint said.

Acton police officers came to the house on Martha Lane at 6:37 p.m. Tuesday to do a welfare check, officials said.

The suspect’s tutor, who had a 4 p.m. appointment at the family home on Tuesday, “was unable to make contact with residents upon arrival,” prosecutors said.

That’s when the suspect’s father — who left the house hours earlier to go to work — called police. Officers “found both victims dead inside,” the district attorney said.

The body of the suspect’s brother was found on the first floor and the body of the mother in the basement, officials said.

“The investigation has so far shown that Arjun had recently been demonstrating some concerning behavior, including using the internet and ChatGPT to make searches for theoretical ideas or fantasy stories regarding the killing of his family,” Middlesex County County DA Marian Ryan told reporters on Wednesday.

Hours earlier, the suspect had typed in ChatGPT, “wait when Adrian kills parents I could see him luring one to convo in basement as they have always forced him to do but what excuse would he use to take their phone” and “maybe before killing mom Adrian coldly reveals,” according to the complaint.

“He was engaged in the use of ChatGPT in creating fantasy stories, kind of the gothic novel kind of stories, asking questions, creating characters, asking what about this if this happened to that, and they seem to appear to relate to threats to his family,” she added.

A rep for OpenAI, the San Francisco-based developer of ChatGPT, could not be immediately reached for comment on Thursday.

It wasn’t clear who was killed first between the two victims. The suspect’s brother “went to a recreational facility” at around 9 a.m. and returned home shortly after noon, the prosecutor said.

“This is an unspeakable tragedy,” Ryan said. “It is an incredibly dark day. Obviously, an insurmountable tragedy for the dad in this case.”

The suspect and his mother’s car, a 2014 green Honda Accord, were missing from the home when the bodies were found, officials said.

An alarm was tripped at a parking lot, about 13 miles away in Wayland early Wednesday morning, officials said.

Responding officers “recognized that license plate and Arjun was inside that car,” Ryan said.

“He was taken into custody by police without incident,” she added.

The suspect was asleep and officers found bedding and “large amounts of cereal and protein energy bars,” according to the complaint.

A person, whose name was redacted from the court document, had been to a nearby supermarket at about 4 p.m. on Tuesday and purchased “an enormous” amount of cereal and energy bars.

“This employee reported this purchased was in excess of $2,000 and when questioned, he reported he had plans to sell the items,” according to the complaint.

Local law enforcement knew the family from when the suspect was briefly reported missing last year.

“It was more of a runaway reported missing child at the time and there there wasn’t much involvement after that,” said Acton Police Chief Douglas Sturniolo, adding that there had been no threats of violence in that previous matter.

Defense lawyer Debra DeWit urged the public to reserve judgement.

“My client is distraught and confused,” she told NBC News on Thursday. “It’s a tragedy for everyone.”

Aravind pleaded not guilty on Thursday and was ordered held without bail.