Roger Hein, 56, killed in semi-truck crash crash into tree on Highway 20 on May 27.

Illinois State Police say Roger Hein, 56, crashed into a tree around 8:00 a.m. Tuesday between Stockton and Lena on Highway 20. Investigators say early reports show he may have suffered some kind of medical attack before the crash. Police are still trying to figure out what went wrong. The highway was closed for nearly ten hours.

UPDATE: A busy Stateline highway is expected to re-open soon. Police say a semi-truck driver is killed after slamming into a tree.
All lanes on U.S. Route 20 between Stockton and Lena have been closed for nearly eight hours.

These photos were taken just west of Freeport by a witness to the crash. Illinois State Police say the driver of the truck went off the road on U.S. 20 close to Sunnyside Road just after 8 a.m. That's about half a mile from the cheese company Kolb-Lena. A witness tells 23 News the truck driver over-corrected and slammed into a tree.

"As soon as I got there, I just saw black smoke," says Alicia Corbin, a witness to the scene of the crash. "Lots of tires because the trailer was carrying really big, tractor tires."

Illinois State Police are still on the scene of the crash.