Authorities say two people died and a third was injured when an 18-wheeler in which they were riding ran off Interstate 12 near Lacombe, struck a tree and caught fire.
State police tell The Times-Picayune the injured person was taken to the Interim LSU Public Hospital in New Orleans with serious injuries.
Identities of the victims were not immediately released.
The tractor-trailer rig ran off the highway's eastbound lanes near the Lacombe exit in St. Tammany Parish.
Police say an 8-year-old boy was killed when a sport utility vehicle he was in lost control in a curve in an off ramp of Interstate 10 in eastern New Orleans.
The Times-Picayune reports that the boy was identified as Adrian Antoine III of New Orleans. Antoine was pronounced dead on the scene.
The driver and three other passengers remained in critical condition Sunday.