Uber Executives were taken in for questioning and arrested on Monday as the government tightens restrictions on the ride-sharing application that has caused taxi drivers to start a protest in the streets of France.

"Two representatives of Uber today went voluntarily to a police hearing that is part of an ongoing legal proceeding. Uber is always willing to work with authorities to overcome possible misunderstandings," said an Uber spokesman in an email, according to Reuters.

The arrested executives - Uber France's CEO Thibaud Simphal and Uber Europe General Manager Peirre-Dimitri Gore-Coty - have previously said that Uber would continue operations in the country until a court rules against their service, UberPOP, according to Fortune.

The concept of the smartphone app is like carpooling. It allows private drivers to pick up passengers using personal cars even without a professional driver's license. The app computes the cost of the travel, but the passenger has the opportunity to negotiate with the driver about the price, something that cannot be done with normal metered cabs.

UberPOP has been deemed illegal in France since 2014 but the country has trouble enforcing because drivers continue to participate since their fines are paid off by Uber itself.

The arrest was made just a few days after taxi drivers in Paris started clogging up the streets as a form of protest, standing by their call that the smartphone app is giving them an unfair competition for passengers.