Ambulances and rescue crews were at the scene of the 20-foot sinkhole at about 8 p.m. near Laurel Canyon Boulevard and Woodbridge Street, Los Angeles Fire Department officials said.
At least one person was trapped when the first vehicle plunged through the hole, until fire crews were able to pull the woman out of the vehicle. The victim was rushed to the hospital in unknown condition, officials said.
Just minutes later, a second vehicle, which was unoccupied, was swallowed up in the hole.
Water was seen raging in the hole underneath the roadway, where the cars were flipped upside down.
Fire officials urged drivers to avoid the area of Laurel Canyon and Ventura boulevards as crews worked to get the vehicles out of the sinkhole.
A San Bernardino County fire truck plunged over the side of the 15 freeway in the Cajon Pass when the rain-soaked roadway gave out.
video shows the truck perched precariously over the side of the freeway, one rear wheel dangling free.
Suddenly the road gives out and the fire engine tumbles over the side.
Firefighters had already evacuated the vehicle and no injuries were reported.
The truck was in that location responding to a report of another vehicle, a big rig, that had also fallen over the side of the road.
The incident happened in the No. 5 lane of the southbound 15, south of the 138, after 8 p.m.