CHICAGO (CBS) — Seven people were rescued overnight from a boat that broke down in Lake Michigan offshore from downtown.

Fire Department crews found the boat about a mile south-southeast of Navy Pier around 12:40 a.m. Thursday, according to a petty officer with the U.S. Coast Guard.

Seven people were aboard the 22-foot aluminum vessel when it broke down and was left crippled, he said.

The passengers had anchored the boat while they waited to be towed to shore. No one was injured.

There is no word on why the boat broke down.

The Sun-Times Media Wire contributed to this report.