Tribune photo illustration

A Chicago Police Marine Unit boat in 2003. (David Klobucar, Chicago Tribune archive photo / May 23, 2003)

A man's body was found in the South Branch of the Chicago River this afternoon, authorities said.

The body of the man, believed to be in his 40s, was found in the river near 600 S. Wells Street, authorities said. The Police Marine Unit was called to the scene about 2:40 p.m., said Chicago Police News Affairs Officer Joshua Purkiss.

The man had not yet been identified Wednesday evening, according to the Cook County medical examiner's office.

Workers with the Metropolitan Water Reclamation District noticed the man's body floating in the river and called 911, police said.

The Marine Unit was able to retrieve the body from the river, and it was brought to the Cook County medical examiner's office.

Detectives are conducting a death investigation. An autopsy is expected to be performed on Thursday.

lford@tribune.com

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