A woman has been arrested on suspicion of causing a massive crash in the Tour de France, according to local reports.
The unnamed woman, brandishing a cardboard sign on the roadside which clipped German rider Tony Martin who fell to the ground, wiped out almost the entire peloton during the first stage.
The crash held up the race for five minutes while bikes and bodies were untangled. As a result, one rider had to pull out of the Tour and another eight riders were treated for injuries.
Video footage of the incident has been shared widely online.
Following the incident, organisers of the event said legal action would be taken against the spectator.
"We are suing this woman who behaved so badly," Tour deputy director Pierre-Yves Thouault told AFP.
"We are doing this so that the tiny minority of people who do this do not spoil the show for everyone," he said.
Authorities say the woman, who is French, is accused of involuntarily causing injury and could be fined up to NZ$25,000 if found guilty.