Authorities is Rhode Island say it is "very possible" a man's body that was pulled out of the Providence River Tuesday is that of missing Brown University student Sunil Tripathi, who was falsely accused of being one of the Boston Marathon bombers on social media websites.

Boston.com reports Providence police Lieutenant Joseph Donnelly says “it’s very, very possible” the body belongs to Tripathi, who has been missing since March 15. He said authorities will not know for sure until the medical examiner's office has a chance to identify the body.

Donnelly says the body was found Tuesday floating in the river by the coach of Brown's rowing team.

WPRI reports authorities believe the body is that of a male between the ages of 20-30, and that it has been in the water more than a couple of days.

Tripathi, 22, originally from Bryn Mawr, Pa., and known as "Sunny," is on leave from the Ivy League school but was living in an apartment in Providence with classmates, his sister Sangeeta told the Associated Press. During his leave, he was volunteering at local libraries and at a chess club.

She said her brother had been acting normally in the days and weeks leading up to March 15, although he was going through a "tough time."

After the Boston Marathon bombings last week, Tripathi's family was rocked by rumors spread on social media websites such as Twitter and Reddit that he could have been one of the suspects, Reuters reports.

"Someone will tweet, then retweet, and completely unsubstantiated things can proliferate so rapidly and destructively,'' Sangeeta Tripathi told Reuters. "Those night hours were horrible."

Reddit has since apologized for the rumor, and on Friday, Reddit users launched a new crowd-sourced campaign to help locate Tripathi.

On the last day he was seen, a Friday, he had tea with a friend, spoke on the phone with his grandmother and had a lengthy text message conversation with his aunt in Boston, which was not unusual, Sangeeta Tripathi said. Around midnight, he traded text messages with his mother.

"All of those people felt nothing remarkably different was happening," his sister said.

On Saturday afternoon, she texted him and didn't hear back.

She says he left his wallet, credit cards and cell phone in his apartment as well as a note that was not addressed to anyone in particular. She would not discuss what it said.

"It was a very short note that was very vague and not conclusive," she said.

Other than his clothing, the only items he appears to have taken with him are a key to his apartment, an old, faded Brown ID and his glasses, Sangeeta Tripathi said.

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The Associated Press and Reuters contributed to this report.