Two senior Uber executives have reportedly been taken into custody in France, as pressure mounts on the company to cease the ride-sharing element of its service.

Paris-based news agency Agence France-Presse issued this announcement at 3 p.m. local time this afternoon.

An Associated Press release confirmed more details of the developing situation, adding that the Paris prosecutor has taken “two Uber managers into custody for questioning over ‘illicit activity’ linked to the ride-hailing company’s low-cost service.”

Though identities of the executives have not officially been revealed, one local journalist reported that it was the “CEO of Uber France” and the “General Manager Europe” at the company.

Today’s news comes amid rising pressure on French authorities to stamp out what critics have called unfair, anti-competitive practices by Uber.

Indeed, UberPop — the local equivalent of UberX in the U.S. — is a ride-sharing service that connects travelers with private car owners. It lets anyone become a taxi driver, with no regulation or licensing, and has raised the ire of taxi drivers across France, with mass protests ensuing. Local taxi drivers view it as unfair — “One rule for us, another rule for them” is the gist of the complaint.

UberPop has been available in Paris and other cities for years, but the latest round of protests seemed to have been provoked by a further rollout of UberPop earlier this month in Marseille, Nantes, and Strasbourg.

UberPop’s legal status has been challenged in France before, and last October a law was passed that apparently banned the practice of connecting riders with unregistered drivers. But Uber continued to offer the service anyway, and even won a temporary reprieve in a Paris court, pending further clarification of existing laws.

While Uber has always been bold with its endeavors to disrupt an industry not always open to innovation, this latest development in its perennial fight with regulators is a notable milestone. But it isn’t the company’s first encounter with the cops. Uber’s Paris offices were raided by police back in March, while in April an Amsterdam-based Uber employee was arrested for failing to “cooperate” with inspectors during a raid on its hub in the Netherlands. Elsewhere, Uber CEO Travis Kalanick was charged in South Korea for running “an illegal taxi ring.”

As a result of the latest wave of protests in France last week that brought widespread disruption, France’s interior minister publicly backed a nationwide ban on UberPop, a move seemingly designed to placate disgruntled taxi drivers. However, with two Uber managers now in police custody, this serves as the clearest indication yet that French authorities are serious about forcing Uber to comply with regulations that some say already prevent the UberPop service from operating in the country.

Update, 8.45 a.m. (PDT) June 29:

An Uber spokesperson has confirmed the above with VentureBeat, telling us that two executives “attended a hearing” with French authorities; they are Pierre Dimitri, general manager for Western Europe, and Thibaud Simphal, general manager for France. The statement read:

Our general managers for France and Western Europe today attended a hearing with the French police. We are always happy to answer questions the authorities have about our service — and look forward to resolving these issues. Those discussions are ongoing. In the meantime, we’re continuing to ensure the safety of our riders and drivers in France given last week’s disturbances.

A source close to the situation in Paris has also confirmed to VentureBeat that while both Dimitri and Simphal attended the hearing voluntarily — they weren’t physically arrested and brought in — they remain in custody and are not free to leave off their own accord. It’s believed that no charges have yet been brought against Uber or any Uber representative.