The condition of one of the victims of a three-vehicle wreck on I-15 Tuesday is improving, but the condition of another is deteriorating, a nursing supervisor said Friday.

Clarence Snyder, 70, was reported in good condition. However, the condition of Bernice Snyder, 69, has been downgraded from fair to serious. The couple is from Ogden.The two were riding in a vehicle that struck a 55-gallon steel drum that apparently fell from a pickup truck in front of them, according to the Utah Highway Patrol. The car swerved into another northbound lane of 1-15 in Centerville.

A propane-fueled car driven by Arthur Kranendonk, 57, Ogden, struck the Snyders' car and was then hit by a tractor-trailer rig, the UHP said. Kranendonk was killed in the explosion when the propane tanks blew up.

No citations have been issued and the investigation is continuing.