The northbound lanes of Interstate 79 near the Warrandale exit are currently closed due to a crash. 

According to the Pennsylvania State Police, a tractor-trailer was traveling south when it crossed the median and crashed into a van in the opposite direction. 

State police tell KDKA-TV that the truck clipped another truck, causing it to cross over the median, and hit the van head-on. 

Three people were taken to the hospital to be treated for their injuries: two from the van and one from the truck. 

Their conditions are not known. 

The southbound lanes were closed for a brief period but eventually reopened. 

As of about noon, the southbound lanes are reopened, but the northbound lanes remain closed. 

State police are telling motorists to avoid the area and find alternate routes. 

This is a developing story. Stay with KDKA-TV and KDKA.com for the latest.