The accident happened 45 kilometers from the finish of the first stage of the race on Saturday -om Brest to Landerneau – when a spectator at the side of the road held up a large sign which caused the piling up.
It’s not clear what she meant on the sign that said ‘GO OPI-OMI!’ in French and German, which translates as “Go grandmother and grandfather”.
According to race video coverage of the incident on Saturday, the sign hit German rider Tony Martin who was riding close to the front of the field. Martin fell, resulting in the subsequent fall of dozens of runners behind him.
Cyclists fell en masse and the crash left bikes and bodies entangled on the road. The fall delayed the race for several minutes.
Gendarmes from Finistère had posted a call on Facebook to find the spectator who had apparently left the scene before their arrival.
On Sunday, the Finistère gendarmerie announced the opening of a judicial investigation for “involuntary injuries of the handicap not exceeding three months by a deliberate violation of an obligation of safety or prudence”.
The woman faces up to two years in prison and a $ 35,000 fine according to the Brest prosecutor’s office.
The opening stages of this year’s Tour were marred by a series of accidents.
On Tuesday, in the fourth stage, the peloton suspended the race for about a minute in a silent protest for safer racing conditions.
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The runners then covered the next 10 kilometers very slowly.