Four people were hospitalized for minor injuries after a 20-car pile up on Interstate 95 Saturday morning.

A truck and tractor-trailer collided on I-95 south near Dale City shortly after 8 a.m., according to Virginia State Police spokeswoman Corinne Geller. That sparked a chain reaction on the snow-covered road, and at least 20 vehicles — including four tractor-trailers — collided, Geller said.