At least three people were killed on a Pennsylvania highway Monday after a fiery collision involving more than 50 vehicles during a snow squall, authorities said.

Schuylkill County coroner Dr. David J. Moylan warned Monday afternoon that the death toll “could run higher” because the search of the scene hadn’t yet been completed because of burning vehicles.

The fiery crash occurred on Interstate 81 at about 10:30 a.m. near Minersville, about 100 miles northwest of Philadelphia, John Blickley of the county’s emergency management office, told USA TODAY. At least 20 people were sent to hospitals with injuries, he said. 

Footage uploaded to social media showed an out-of-control tractor-trailer smash into a large dump truck, turning it nearly 180 degrees. Another large truck spewed black smoke and orange flames into the air and an SUV struck a passenger car sending the sedan spinning, narrowly missing its driver who stood on the shoulder of the highway shrouded in snow and fog.