A woman was killed in a fiery crash involving two tractor-trailers on a Bronx expressway early Tuesday, authorities said. 

One of the tractor-trailers, a contracted vehicle carrying US mail, was heading south on the Cross Bronx Expressway – underneath University Avenue – around 12:30 a.m. when an unidentified woman driving a Range Rover rear-ended the truck, cops said. 

Both drivers remained at the scene and were stopped in the center lane when a second tractor-trailer slammed into the Range Rover from behind, police said. 

The impact propelled the SUV partially into the back of the first truck, and caused it to flip over, cops said. 

All three vehicles became engulfed in flames. 

First responders found the woman still inside her Range Rover. She was pronounced dead at the scene, police said. 

The truck drivers were uninjured, authorities said. No arrests have been made. 

Video posted to Citizen shows heavy smoke and flames billowing from one of the tractor-trailers. 

Photos show one of the trucks completely burned out, reduced to a mere frame. 

Other videos show the roadway blocked off as multiple FDNY vehicles responded to the scene.