A Plainfield man who was reported missing for nearly a week was found dead near a crashed car Saturday along I-55 in southwest suburban Joliet.

Authorities responded to reports of a rolled-over Buick LaCrosse at 8:47 a.m. Aug. 17 off of I-55 near the ramp to U.S. Route 30, according to Illinois State Police.

Troopers searched the tall grass in the area and found the body of a 28-year-old Plainfield man who had been reported missing to Joliet police on Aug. 11, state police said. Further investigation revealed the Buick was reported stolen from Tinley Park on Aug. 7.

The man had apparently been driving the car when he was ejected during the rollover crash, according to the Will County coroner’s office. The preliminary results of an autopsy indicated he died of multiple injuries from the crash, but a final ruling on the cause and manner of his death is pending toxicology testing and further investigation.

It was not immediately clear when the crash occurred. The case remains under investigation by state police.