A 17-year-old boy in Massachusetts, United States, allegedly killed his mother and 14-year-old brother after using ChatGPT to search for “theoretical ideas or fantasy stories regarding the killing of his family,” prosecutors said.

Arjun Aravind, 17, of Acton, a Boston suburb, was charged with two counts of murder over the deaths of his mother, Sudha Venkatesan, 45, and his brother, Siddharth Aravind, 14.

He was also charged with assault and battery for allegedly using “a dangerous weapon, a Laptop,” to attack the two victims, according to a criminal complaint filed in Concord.

Investigators said they found “a heavily damaged bloody laptop computer” at the family’s home, which they believed was used during the attack.

Police also found what appeared to be a knife.

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

What happened

Acton police officers went to the family’s home on Martha Lane at about 6:37 p.m. Tuesday for a welfare check.

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

Shortly afterwards, Aravind’s father, who had left for work hours earlier, called police.

Officers then “found both victims dead inside,” Middlesex County District Attorney Marian Ryan said.

Siddharth was found on the first floor, while his mother was found in the basement.

The complaint said the boy was found “with massive trauma to the head” and “lying in a pool of blood.”

Venkatesan was found with “heavy trauma” to her head and face. She also had “a puncture rod to her stomach consistent with some object being used as a weapon,” according to the complaint.

“As officers cleared the residence, significant biological evidence was observed in and around the bodies,” the probable cause statement said.

ChatGPT searches before the killings

Prosecutors said Aravind had used ChatGPT hours before the killings to write about fictional characters killing their parents.

According to the complaint, he typed: “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”

He also wrote: “maybe before killing mom Adrian coldly reveals,” according to the complaint.

Ryan said Aravind had recently shown what investigators described as concerning behaviour involving the internet and ChatGPT.

“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,” Ryan told reporters on Wednesday.

A representative for OpenAI, the developer of ChatGPT, could not immediately be reached for comment.

Ryan said the searches appeared to involve fictional stories and characters but were linked to threats involving Aravind’s family.

“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,” Ryan said.

Family had reportedly hidden knives

According to the complaint, Aravind had been experiencing “behavioral issues” and had been involved in “concerning internet activities.”

The family had reportedly been hiding knives in the house to stop him from getting access to them.

Ryan said it was unclear which victim was killed first.

Siddharth had gone to a recreational facility at about 9 a.m. and returned home shortly after noon on the day of the killings.

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

17-year-old arrested in family’s car

After the killings, Aravind and his mother’s 2014 green Honda Accord were missing from the home.

An alarm was triggered at a parking lot about 13 miles away in Wayland early Wednesday.

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

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

Aravind was found asleep inside the vehicle. Police also 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 gone to a nearby supermarket at about 4 p.m. Tuesday and bought “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,” the complaint said.

Previous contact with police

Police had previously dealt with the family after Aravind was reported missing in 2025.

Acton Police Chief Douglas Sturniolo said the incident was treated as a runaway case and involved no threats of violence.

Aravind’s lawyer, Debra DeWit, urged the public not to reach conclusions before the case is heard.

“My client is distraught and confused,” she said. “It’s a tragedy for everyone.”

Aravind pleaded not guilty on Thursday and was ordered to remain in custody without bail. (Sunday Tribune)

•Arjun Aravind and his lawyer Debra DeWitt during his arraignment in Concord, Massachusetts, on Thursday. (Photograph: Lane Turner/The Boston Globe/AP)

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