Eleven people have died and 29 were injured on October 9 in three crashes involving multiple vehicles in Serbia, police said.

A police statement said that dense morning fog was the cause of two of the crashes on the main north-south highway in central Serbia, which resulted in seven people being killed and and 27 injured.

The accidents happened on both sides of the highway about 110 kilometers southeast of the capital, Belgrade.

The statement said the crashes involved 34 cars and trucks.

Earlier, Serbian television reported that some victims were stuck in their cars and needed to be pulled out by rescuers, while traffic was halted in both directions.

An unidentified truck driver told state TV that the fog was "dense as a wall."

The third crash occurred in the evening on a local road in the same general area and involved two trucks and a car.

Four people were killed and two injured, police said, without mentioning what might have caused the collision.

With reporting by AP