Team Sky say that “thousands” of spectators were the root cause of an incident on Mont Ventoux that caused Chris Froome and the other leaders to crash.

Richie Porte (BMC Racing) crashed into a motorbike that had to brake for crowding fans around 1.5 kilometres to race on the 9.7-kilometre closing climb. Froome and Bauke Mollema (Trek-Segafredo), the other two leaders, fell as well.

Froome had to run with his bike broken and lost time when first trying to use a neutral bike and then switching to his own.

It appears that the race jury has neutralised the result, and in fact Froome appears to have increased his lead in the general classification, but the chaotic scenes turned what should have been a race-defining stage into a farce.

“It’s crazy, there’s nothing to do with the weather or the barriers,” Sky Sports Director Nicolas Portal said.

“It’s a shame about what happened. It’s not just one spectator, it’s about thousands. It’s not one, two or 10. It gives me the shits.

“We’ve been animated the race, and today we were on the offensive, creating splits. And now this happens.”

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Froome ran for around 40 seconds until he took a Mavic neutral service bike. It was too small and he had to stop again. The chasing group behind the trio caught and passed Froome and Porte.

Adam Yates (Orica-BikeExchange) placed behind Mollema and was marked as the provisional race leader, but he is now 47 seconds behind Froome in second place.

“There was a wall of people, and we just couldn’t get through. The Sky car was blocked by the commissaires car, and we couldn’t get through,” Portal added. “It’s more than just a mechanical, we couldn’t get even get through to him. It’s just crazy.”