The police faced off Thursday with taxi drivers blocking access to the Paris ring road. Similar protests were held in other cities.

The French interior minister, Bernard Cazeneuve, who met Thursday evening with the taxi unions, deplored the violence, but saved his most angry words for Uber. He said the company behaved with “arrogance” in its flouting of French law and declared that “the government will never accept the law of the jungle,” referring to Uber’s stark form of competition.

With blocked streets and fights still breaking out in several parts of Paris in the early evening, many Parisians were scrolling on their smartphones to find other routes home. And unsuspecting visitors found themselves inadvertently caught up in an increasingly heated labor dispute. Many turned to social media during the day to share their ordeals.

The singer and actress Courtney Love assailed Paris as an unreliable destination when she posted on Twitter, to her nearly 2 million followers, about being caught in the protests. “They’re beating the cars with metal bats,” Ms. Love wrote. “This is France? I’m safer in Baghdad.”

Ms. Love, the widow of the Nirvana frontman Kurt Cobain, wrote on her social media timelines that she and her driver were held hostage on her way from the airport until she was rescued by passing motorcyclists. It is not clear if she was using Uber’s service at the time.

Other visitors to Paris could be seen trudging toward the airports hauling large suitcases, and on the Métro with strangers helping them to navigate the stairs. Some tourists seemed completely confused about why there were no taxis in Paris on Thursday.

Ian Langsdon/European Pressphoto Agency nytimes.com

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