Chicago police launched an investigation after pulling a man’s body from Lake Michigan on the city’s South Side. The discovery came around 5:11 p.m. Saturday in the 5400 block of South DuSable Lake Shore Drive, close to Hyde Park.

A witness spotted the man unresponsive in the water and alerted authorities. Officers from the Chicago Police Marine Unit responded quickly. They retrieved the body from the lake. Paramedics pronounced him dead at the scene.

Police described the victim as a male of unknown age. They have not released his identity. No other details about the circumstances surfaced immediately.

The South Side location sits along a busy stretch of the lakefront, popular for recreation. DuSable Lake Shore Drive carries heavy traffic there, with Hyde Park’s residential neighborhoods just inland. Investigators have not said if foul play is suspected or how the man ended up in the water.

Chicago police offered no additional information late Saturday. The case falls under routine procedure for water recoveries in the massive Lake Michigan, which borders the city for 22 miles. Marine Unit teams handle such calls regularly, often involving drownings or accidents.

Authorities typically withhold names until next of kin get notified. An autopsy will determine the cause of death. Cook County medical examiner’s office staff will conduct it, as they do for most Chicago fatalities.

Witnesses rarely spot bodies in the lake without prompting questions. Swimmers, boaters or joggers along the shore sometimes make the finds. This one drew a swift response from marine officers stationed nearby.

Police asked anyone with information to call detectives. The investigation continues amid Chicago’s typical weekend activity along the lakefront. No related incidents were reported in the immediate area.