June 20 (UPI) -- At least two people died and two were seriously injured in a fiery accident involving multiple vehicles on a Wisconsin freeway, authorities said.
Racine County Sheriff Christopher Schmaling told reporters the accident occurred around 11 a.m. Wednesday when police received multiple 911 calls of fire and explosions on Interstate 94, part of which was under construction.
According to preliminary investigations, the accident occurred when the driver of a semi-trailer truck hit a construction barrier while switching lanes. Officials say he over-corrected and hit the center median.
"Given the size and scope of that vehicle and interstate speeds, [he] literally shoved that median wall into now the northbound lanes," Schmaling said. "As a result, three passenger vehicles also collided with one another, with the barriers, with the wall itself."
A second semi-trailer truck went off the road and burst into flames, Schmaling said. Both truck drivers died and two other drivers were hospitalized in serious condition. Police are unsure if there were other occupants in the trailers, he said.
"In my 24 years on this job, this is the worst accident I've ever been a part of," Schmaling said.
The explosions reported are believed to have been the result of tires popping from the heat of the fire, but the contents of the semi-trailer trucks will be investigated, he said.
Schmaling said the driver of the second semi saved lives by driving off the freeway.
"By avoiding a crash of three individuals and a semi-tractor trailer already involved in a crash and turning to avoid all that -- absolutely [he saved lives]," he said. "I think this unfortunate deceased individual is a hero."