Two women in critical condition after boat accident in Chicago's 'Playpen' on Lake Michigan

Two women are in critical condition after a boat accident on Lake Michigan in an area known as Chicago's "Playpen."

The "Playpen" is the nickname for an area north of Navy Pier where boaters anchor. It can be a party scene, with people sometimes jumping or swimming from boat to boat.

The Chicago Fire Department said that their preliminary information shows that the victims were in the water when a boat backed into them.

The victims were taken to Northwestern Hospital where they were listed in serious-to-critical condition, fire officials said.

Chicago's Playpen on Lake Michigan north of Navy Pier. File photo from photographer Taylor Glascock/Bloomberg via Getty Images