(STMW) — An 80-year-old man died Friday morning after he apparently jumped off a bridge into the Des Plaines River in southwest suburban Joliet, the coroner’s office is reporting.

The unidentified man was pronounced dead at 7:41 a.m. at Saint Joseph Medical Center in Joliet, according to the Will County coroner’s office.

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He was witnessed jumping off the Cass Street Bridge into the Des Plaines River, the coroner’s office said.

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An autopsy performed Saturday ruled his preliminary cause of death as drowning, but the final cause and manner of death will be determined at a later date pending toxicological and police studies, authorities said. The man’s name has been withheld, pending notification of his family.

Joliet police are investigating the death.

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