A 90-year-old man died Saturday, a month after he was injured in a crash on the Dan Ryan Expressway on the South Side.

The crash happened about 10:35 a.m. March 14 in the southbound lanes of the Dan Ran near 64th Street, according to Illinois State Police and the Cook County medical examiner’s office.

Huu Trac Huynh, 90, was a passenger on a motor coach that struck a semi tractor that had slowed down to move into another lane because of equipment problems, according to ISP Master Sgt. Jason Bradley.

Eleven people were taken to hospitals after the crash with what were believed to be non-life-threatening injuries, police said.

Huynh, a Lincolnwood resident, was initially treated and released from St. Bernard Hospital, but was later admitted to Stroger Hospital, where he died at 4:58 p.m. Saturday, authorities said.

An autopsy Sunday found he died of complications of multiple injuries from the crash, and his death was ruled an accident.