NEW DELHI, Jan. 2 (Xinhua) -- At least four people have been killed and four others injured in a road accident in the western Indian state of Rajasthan Tuesday, police said.

"The accident occurred when a car in which the victims were travelling suddenly plunged into a large pond in the state's Bharatpur district," a police official said.

While four bodies were fished out of the pond, those injured have been admitted to a nearby government hospital where the condition of one is said to be serious, he said.

Eye-witnesses told cops that the vehicle fell into the Bharatpur dig after its driver failed to spot the waterbody due to low visibility owing to dense fog in the area.

A probe has been ordered into the incident, the official added.

India has the highest number of road fatalities in the world. Road accidents occur mostly due to poor driving or badly maintained roads and vehicles.