French news outlet AFP reported that the Marseille prosecutor’s office announced the opening of the formal investigation on Monday (AEST), following the final stage of the race in which Tadej Pogačar claimed the yellow jersey.
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Prosecutor Dominique Laurens confirmed the search led to the, “discovery of many health products including drugs (...) and especially a method that could be qualified as doping."
Newspaper Le Parisien reported a team doctor and soigneur (physio) had been taken into preliminary custody after "100ml of saline and injection equipment" were discovered in the searches. Nairo Quintana and Dayo Quintana were also reportedly questioned after the arrests.
The search was conducted at the team hotel in Méribel by officers from the Central Office for Combating Environmental and Public Health Damage (OCLAESP) after stage 17 on the Col de La Loze, with newspaper L'Equipe reporting the rooms of riders Nairo, Dayo and Winner Anacona were searched as well as those of team phyisos and the team cars.
The UCI released a statement in support of the investigation noting it would become more involved when more information came to light.
"The UCI confirms that it has been in communication with OCLAESP and the Cycling Antidoping Foundation (CADF) as part of the legal operations carried out by the French authorities on the sidelines of the Tour de France," the statement read. "The UCI welcomes and supports the action of all parties involved and will take the appropriate measures once it has taken note of the information obtained by the French legal authorities."
Team Manager Emmanuel Herbert commented on the situation in a statement on Arkea-Samsic's website, confirming the search had taken place and that the team would be distancing themselves from acts of doping if they were found to have been committed in the investigation.
"A search was carried out last week in our hotel, as I have already confirmed with various media. It only involved a very limited number of riders and their close relatives who are not employed by the team," Hubert said.
"We obviously support our riders, but if it turns out that, at the end of the ongoing investigation, elements confirming the veracity of doping practices, the team will immediately disassociate itself from such acts and will immediately take the necessary measures to put an end to the links that could unite them with unacceptable methods that are still being fought against."