A pileup during a spring snow squall in Pennsylvania on Monday involving 50 to 60 vehicles killed at least three people and resulted in multiple injuries, officials said.

A portion of Interstate 81 about 100 miles northwest of Philadelphia was closed until further notice and at least 20 people were transported to local hospitals, according to Schuylkill County Emergency Management.

Three people died in the accident, according to John Mika, Schuylkill County Coroner’s Office.

A collision involving as many as 40 vehicles closed a portion of Interstate 81 in Pennsylvania on Monday, according to the Schuylkill County Office of Emergency Management.WBREA collision involving as many as 40 vehicles closed a portion of Interstate 81 in Pennsylvania on Monday, according to the Schuylkill County Office of Emergency Management.A collision on I-81 in Pennsylvania on Monday.WBREA collision involving as many as 40 vehicles closed a portion of Interstate 81 in Pennsylvania on Monday, according to the Schuylkill County Office of Emergency Management.A collision on I-81 in Pennsylvania on Monday.WBRE

Fire rescue teams, state police and Pennsylvania Department of Transportation staff responded to the scene, which occurred between exits 116 and 119. 

Pennsylvania State Police said a large fire involving several vehicles were burning.

It’s unclear what first caused the pileup, but it appears low visibility due to the late-season snow storm was a contributing factor.

Video showed vehicles pulled to the side of the road being hit by oncoming traffic as heavy fog covered the interstate. Large black smoke plumes rose from what appeared to be a vehicle on fire, based on video taken by someone saying they were involved in the crash after they exited their car.

This is a breaking story, please check back for updates.