MURRIETA (CNS) - A fire erupted in the engine of a tractor-trailer on Interstate 15 in Murrieta Friday, spreading quickly until most of the rig was engulfed, but the driver escaped injury.The fire was reported at 11:10 a.m. on the southbound side of I-15, near the off-ramp to Murrieta Hot Springs Road, according to the California Highway Patrol.Murrieta Fire & Rescue crews reached the location within a few minutes and encountered flames raging in the big rig's engine compartment. The fire spread to the cab and one of the trailers before crews knocked down the flames, according to the CHP.A SigAlert was issued at 11:27 a.m. as traffic backed up because of a lane closure and attention drawn to the blaze. As of 2 p.m., traffic was snarled on southbound I-15 all the way back to
