French authorities have issued arrest warrants for Telegram CEO Pavel Durov and his brother, Nikolai, in March, according to a French administrative document cited in a report by Politico.

The document shows, according to the same publication, that the French secret investigation into Telegram is broader and began months earlier than previously known. The case revolves around Telegram’s refusal to cooperate with a French police investigation into child sexual abuse.

Pavel Durov was arrested on Saturday night by the French police at the airport Le Bourget of Paris, after border guards had alerted judicial authorities that he was arriving on his private jet from Azerbaijan.

His arrest has sparked diplomatic jousting for the French government as well as global outcry centered on both the debate over free speech and the culpability of social media for the material shared by its users.

The arrest warrants were issued after the messaging platform gave “no response” to a previous court request for Telegram user identification, according to the document, which was shared with Politico by a person directly involved in the case.

The document also highlights “Telegram’s almost non-existent cooperation” with both French and European authorities in other cases.

Warrants for Pavel and his brother Nikolai, a co-founder of the platform, were issued on March 25 on charges that include “complicity in the possession, distribution, offering or distribution of pornographic images of minors to an organized group.” French media had previously reported that the investigation was opened in July.

The warrants were issued following an undercover investigation into Telegram led by the Paris prosecutor’s office investigating cybercrimes, which involved a case in which a suspect solicited “material related to child pornography” from underage girls and then threatened publicize it on social media.