Five nursing students died Wednesday in a chain-reaction crash that began when a tractor-trailer failed to slow down and smashed into stop-and-go traffic, Georgia authorities said. The tractor-trailer plowed into an SUV and then rolled over a small passenger car that burst into flames, Sgt. 1st Class Chris Nease of the Georgia State Patrol said. The big truck came to a halt after ramming the back of a tanker. Those killed were travelling on Interstate 16 near Savannah in two passenger vehicles. The cars were mangled by the crash.