Dozens of vehicles crashed on an expressway during heavy fog that caused poor visibility during morning rush hour, as this dramatic footage shows.

The chain collision happened on the Jinan-Qingdao Expressway within the city limits of Zibo in Shandong, China, on Tuesday morning, March 26.

Vehicles were clustered together, with people trapped inside the cars shouting for help, as eyewitness Mr Zhang recounted.

Footage from the scene showed several vehicles on the expressway badly damaged, including cars and lorries, with people standing on the highway guardrail waiting for rescue.

Zhang said the accident occurred due to heavy fog around 6am that morning. Visibility was extremely low, Zhang said, leading to multiple vehicle collisions.

The number of crashed vehicles made for a very challenging rescue, Zhang said.

Locals who witnessed the incident immediately alerted emergency services.

Police cars, fire lorries, and ambulances rushed to the scene, and the injured were immediately transported to hospitals for treatment.

Meanwhile, road authorities worked to gradually remove the vehicles involved in the accident from the scene.

In the evening, the Zibo Traffic Police said in an official statement there were no casualties or serious injuries in the incident.

The expressway has since resumed normal traffic, police added.