EAST ST. LOUIS, Ill. (AP) – A commuter van carrying workers from two aerospace companies collided head-on with a tractor-trailer Friday on a Mississippi River bridge, killing four people in the van and injuring four others, authorities said.

State police said the van was on the Martin Luther King Bridge before dawn when it struck the 18-wheeler, spilling diesel fuel that caught fire near the Illinois end of the bridge. The flames were quickly extinguished.

The wreck closed the busy, four-lane bridge between East St. Louis and St. Louis for about five hours. The bridge is one of three crossing the river at St. Louis.

One victim worked for GKN, a British aerospace business with operations in the St. Louis area; the other three who died, including the van driver, worked for Boeing Co. at its St. Louis aircraft plant.

Boeing spokeswoman Lynn Steinberg said the van was carrying seven people, five Boeing employees and two from GKN.

The truck driver was hospitalized in stable condition, and the three injured commuters were hospitalized with conditions ranging from critical to fair.

The 15-seat van was leased to Boeing by Illinois’ Madison County Transit under a program that provides vans to groups of commuters for a monthly fee, transit spokesman Joe Wright said.