HUDSON - A semitrailer truck that apparently failed to reduce speed on Interstate 39 when traffic slowed for an accident Friday night crashed into several vehicles, sending 10 people to area hospitals and snarling traffic for hours, police said Saturday. | Video

An initial crash was reported around 9 p.m. around three miles north of Hudson on northbound I-39, near mile marker 8. The semitrailer truck failed to reduce speed as traffic slowed for that initial crash, and it plowed into several vehicles around 9:30 p.m. about two miles south of the original crash site, Illinois State Police said in a statement Saturday.

In all, seven vehicles - three semis and four passenger vehicles, including one towing a trailer - were involved in the crashes. Ten people were transported to area hospitals by ambulance and helicopter, two or three of them critically injured, authorities said.

All lanes of Interstate 39 in both directions were reopened Saturday morning, and state police were continuing their investigation into the crash due to the number of victims and vehicles involved.

"It will probably be morning before we figure out how this happened," state police Trooper R. L. Ross said at the scene late Friday night.

After the crash

Driver Rigoberto Garcia of Madison, Wis., who said he was moments away from colliding with the wreckage himself, described it as a chain-reaction crash. He said he saw one car smash into the back of the semi. It was smoking but it didn't catch on fire, he said.

Garcia said the scene was unexpectedly calm right after the accidents. People were surrounded by debris and wreckage, but the scene was almost silent, he said.

"It was weird," he said.

Rescue crews worked to free multiple victims from their vehicles after the crash. One car was trapped under the rear of one of the semitrailer trucks, and vehicles were strewn across the median, ditches and into other vehicles.

Firefighters gathered around a victim on the ground near a semitrailer truck that had run up onto an embankment toward the front of the accident scene.

Bystanders and a state trooper worked to free people from a car that was sitting by itself at the center of the scene.

One semitrailer bearing the Target store label had the back of its trailer ripped off. It appeared to be empty.

Two Life Flight emergency medical helicopters took off from the scene, the last leaving about 10:30 p.m. Police had cut away a fence to allow access from the roadway to an open field where the helicopters landed.

In addition to state police, other agencies at the scene were Normal police, El Paso police, Bloomington police, McLean County sheriff's department, Hudson police, Carlock fire and ambulance, El Paso fire and ambulance, Hudson fire and ambulance and the state Department of Transportation.

Police have not released the names of the victims.

Sharon K. Wolfe, David Proeber, Roger Miller and Ryan Denham contributed to this report.