A horror pile-up involving a truck has left at least 15 dead in California.

The crash in Imperial County is being treated as a 'mass casualty event' by the emergency services.

A vehicle slammed into the 'direct path' of a truck driving on the State Route 115 earlier today.

Juan Rodelo, a fire chief, said the smash happened at the intersection of Highway 115 and Norrish Road, NBC reports.

Judy Cruz, head of the local emergency department, said 14 people had died at the scene with another passing away shortly after arriving at hospital, according to CNN.

The horror crash took place in Imperial County, California

Early reports claim a vehicle carrying 27 passengers crashed into a truck full of gravel. 

Police are investigating the cause of the crash, which took place around 10 miles east of El Centro and near the Mexican border.

El Centro Regional Medical Center CEO Adolphe Edward said: "Patients are going through a difficult time as you can imagine.

At least 15 people have died in the smash, a hospital official said
Police are investigating the cause of the crash

"This was a major accident and we are taking care of them in the emergency room department."

It comes just weeks after a horrific 50-car pile-up on the I-35 motorway in Texas.

Multiple people died in the crash, with dozens more injured, officials said.

In one image, a Coca Cola semi truck was seen badly damaged after it rammed into a black car.

In other photos cars could be seen lifted high off the road surface after being rammed onto other vehicles.

A semi-truck was seen sitting on top of a roadway barrier, over a sheer drop, in what authorities again called a 'mass casualty incident'.