A woman died after a beam fell onto two cars on the 10 Freeway in Ontario early Thursday, according to the California Highway Patrol. 

According to preliminary information, a Kentworth tractor that was pulling a flatbed trailer combination carrying a large excavator crashed into the Interstate 15 overpass. 

The crash caused a metal beam to fall onto two vehicles. 

The beam fell onto the vehicle of a woman who was also driving westbound on the freeway. A man who was also headed westbound then crashed into the beam, the CHP said. 

Both the man and the woman were transported to a medical center with major injuries. The woman was pronounced dead shortly before 7 a.m. 

The driver of the tractor, identified as a 50-year-old man from the city of Mira Loma stayed at the scene during the investigation. 

According to CHP, alcohol or drugs were not suspected to be a factor in the crash. 

The westbound 10 Freeway was closed as cleanup and the investigation continued.