Arjun Aravind, 17, has been charged with two counts of murder following the deaths of his mother and teenage brother

Siddharth Aravind, 14, and Sudha Venkatesan, 45, were found dead in their Acton, Mass., home on Tuesday, Aug. 11

During their investigation, local police discovered Arjun had been displaying "concerning behavior," such as "using the internet and ChatGPT to make searches including for theoretical ideas or fantasies regarding killing his family," the Middlesex District Attorney's Office said in a news release

A 17-year-old boy has been charged with murder after his mother and teenage brother were found dead in their Acton, Mass., home.

Arjun Aravind, 17, is facing two counts of murder and two counts of assault and battery on a household or family member, following the deaths of his mother, Sudha Venkatesan, 45, and his brother, Siddharth Aravind, 14, Middlesex District Attorney Marian Ryan and Acton Police Chief Douglas Sturniolo confirmed in a news release and press conference on Wednesday, Aug. 12.

Acton Police were alerted to the family home just before 6:40 p.m. local time on Tuesday, per the D.A.'s release. Arjun's father had called police after he couldn't reach his family. He hadn't spoken with his wife since about 7 a.m. that morning, when he left for work. Siddharth was last seen leaving a local rec center around 12 p.m., Ryan said in the press conference.

A tutor was also outside the home for a scheduled session but hadn't been able to get in touch with the residents inside when Arjun's father called police.

When police arrived, they found Siddharth's body on the first floor and his mother's in the basement.

"The subsequent investigation indicates that Arjun had recently been demonstrating concerning behavior including using the internet and ChatGPT to make searches including for theoretical ideas or fantasies regarding killing his family," Ryan said in the news release, adding, "It is alleged that Arjun fatally assaulted his mother and brother inside their home yesterday before fleeing the scene."

Authorities determined Arjun had allegedly left the home in his mother's 2014 green Honda Accord. After being unable to find him, they put out an alert for Arjun and found him on Andrew Avenue while responding to an unrelated call about an alarm on Wednesday morning.

Ryan reiterated in the press conference that Arjun was allegedly "engaged in the use of ChatGPT, in creating fantasies, stories, gothic novel kind of stories" and "asking questions, creating characters" that appeared to "relate to threats to his family not surviving."

The Chief Medical Examiner will determine the victims' official cause of death; however, authorities noted the victims did experience some level of trauma and are investigating what kind of weapon was used.

Arjun is also charged with two counts of assault and battery, use of a vehicle without authority and theft of a motor vehicle, per the D.A.'s office. He is expected to be arraigned on the murder and assault-related charges in Concord District Court on Thursday, Aug. 13. He was set to be arraigned on the remaining charges in Lowell Juvenile Court on Wednesday. (The Juvenile Court does not have jurisdiction over the murder charge, according to the D.A.)

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It is not clear if he has retained an attorney to comment on his behalf.

"This is an unspeakable tragedy," Ryan said in the press conference. "It is an incredibly dark day. Obviously an insurmountable tragedy for the dad in this case. It is a very dark day for this community, for this school system."

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