FULLERTON, Calif. (KABC) -- Some deliveries may be delayed after a FedEx truck loaded with packages caught fire along the 57 Freeway in Fullerton.Firefighters with the Metro Cities Fire Authority responded to the scene on the southbound side of the freeway near Yorba Linda Boulevard around 2 a.m. Sunday. Crews were seen working to extinguish the flames spewing out from the truck's back trailer.It's unclear exactly how much was destroyed but several charred packages were pulled out from the truck, some wrapped in Christmas paper. Bottles of wine and even a prepared pie were seen on the pavement of the freeway.No injuries were reported and a cause of the blaze has not been determined.