"It's very, very possible" that the body could be Tripathi's, Donnelly said, adding that authorities will not know for sure until the medical examiner's office in Providence identifies the body.
Donnelly said Tripathi's family has not been notified of the body's recovery, Boston.com reported.
Last week, the Brown University student was falsely accused of being one of the Boston Marathon bombers on social media websites.
An initial police sweep of Tripathi's room found his cellphone, credit card, ID, and other personal items, but his sister said his glasses and Philadelphia Eagles wool cap were gone.
The FBI has been assisting Providence police in the investigation, said Special Agent Greg Comcowich, a spokesman for the FBI's Boston division, last month.
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