French police searched the premises of X in Paris on Tuesday as prosecutors issued a summons to the social media company’s owner, Elon Musk, raising the stakes in a yearlong investigation that has hei...

French authorities raided the Paris office of Elon Musk’s X and summoned the billionaire for a “voluntary interview,” a major escalation of European regulators’ battles with the social-media platform.

The prosecutor’s cybercrime unit is conducting the raid, it said in a statement, with Europol also involved.

Spain’s plan to restrict children’s access to social media has triggered a sharp public clash between Prime Minister Pedro Sánchez and tech billionaire Elon Musk, as European governments harden their ...