Updated on: April 27, 2026 / 2:50 AM EDT / CBS News
Human remains were found in Tampa Bay waterways as authorities continued searching for missing University of South Florida doctoral student Nahida Bristy, Florida deputies announced late Sunday. The remains, recovered in Pinellas County, have not yet been identified. The Hillsborough County Sheriff’s Office said they were located “in the area of Interstate 275 and 4th Street North,” on the St. Petersburg side of the Howard Frankland Bridge.
Bristy, 27, is presumed dead. She disappeared last week along with 27-year-old Zamil Limon. Limon’s remains were recovered Friday on a bridge near Tampa. Limon’s roommate, 26-year-old Hisham Abugharbieh, was arrested Saturday and charged with two counts of premeditated first-degree murder with a weapon; he is being held without bond.
New court documents allege Abugharbieh asked the AI chatbot ChatGPT how to dispose of a body in the days before Bristy and Limon went missing. According to the documents, on April 13 he asked ChatGPT what would happen if someone was “put in a black garbage bag and thrown in dumpster.” The chatbot replied that it sounded dangerous, and Abugharbieh allegedly followed up, “How would they find out.”
Prosecutors say Limon’s body “was located within numerous black utility trash bags in advanced stages of decomposition” on the Howard Frankland Bridge. They allege Bristy was “disposed of in a similar way.”
Court records also say Abugharbieh posed other questions to ChatGPT: on April 15 he asked, “Can a VIN number on a car be changed?” and, “Can you keep a gun at home with out a license.” Just after midnight on April 17, he allegedly asked if cars are “checked at the Hillsborough River state park.” That same night, the documents say, his phone pinged at the location on the bridge where Limon’s remains were later found.
An autopsy by the Pinellas County Medical Examiner’s Office determined Limon suffered numerous lacerations and stab wounds; the manner of death was ruled a homicide due to “multiple sharp force injuries,” the court documents state. Abugharbieh also had multiple lacerations on his body, including on both legs, the filings say.
Detectives used an “enhancement agent” at the apartment shared by Limon and Abugharbieh and reported finding “significant” blood patterns from the entry foyer through the kitchen, into the hallway and inside the suspect’s bedroom. The blood in the bedroom appeared in “two distinct patterns on the floor which appeared to have a relatively human-sized shape,” according to the documents.
Abugharbieh is represented by a public defender. CBS News sought comment after his arraignment but has not received a response. He is scheduled to return to court Tuesday.
Zamil Limon and Nahida Bristy, both 27, were last seen in the Tampa area on April 16, the University of South Florida Police Department said. Families of Limon and Bristy have been identified by authorities.