A seven-year old boy was killed on Wednesday after being struck by a car in the Tour de France's publicity caravan, official sources said.

A helicopter was rushed to the scene but firemen said the child was declared dead before he could be flown to Bordeaux's main hospital.

The accident happened in the village of Retgons, 16 miles (26km) into the 10th stage of the race, from Bazas to Pau in the south-west of France.

According to police the child stepped out in front of the car as he went to cross the road and join his grandmother on the other side.

Following the accident Tour director Jean-Marie Leblanc addressed the caravan over the internal Tour Radio.

Open roads

He said: "This accident must remind all the people who are following the Tour that the roads of the race are dangerous and that they must be very careful. "

The roads followed by the Tour de France are open to the public most of the time without the protection of fences.

Two years ago, a 12-year-old boy was killed by a car overtaking the caravan in Draguignan.

Last year, a car driver crashed into the crowd and injured four people at the finish line of the eighth stage in Pontarlier.