Messaging app Telegram said its CEO Pavel Durov, who was detained in France, had "nothing to hide".
Durov was arrested at an airport north of Paris for crimes related to the operation of the application.
The investigation is reportedly related to insufficient moderation, with Durov accused of failing to take measures to curb criminal use of Telegram. The app has been accused of not cooperating with law enforcement about drug trafficking, child sexual content and fraud.
In a statement, Telegram said its "moderation is within industry standards and is constantly improving."
"It is absurd to claim that the platform or its owner is responsible for its abuse," the app said.
Telegram said Durov travels frequently in Europe and added that he complies with European Union laws, including the Digital Services Act, which aims to ensure a safe and responsible online environment.
"Almost one billion users worldwide use Telegram as a means of communication and as a source of vital information," the app said in a statement.
"We look forward to a quick resolution to this situation. Telegram is with you all."
According to judicial sources quoted by the AFP news agency, Durov's detention was extended on August 25 and can last up to 96 hours.
Pavel Durov, 39, was born in Russia and now lives in Dubai, where Telegram is based. He holds dual citizenship in the United Arab Emirates and France.
Telegram is especially popular in Russia, Ukraine and the countries of the former Soviet Union.
The app was banned in Russia in 2018 after it previously refused to hand over user data. The ban was lifted in 2021.
Telegram ranks among the major social media platforms after Facebook, YouTube, WhatsApp, Instagram, TikTok and WeChat.
Durov founded Telegram in 2013. He left Russia in 2014 after refusing to comply with government demands to shut down opposition communities on his VKontakte social media platform, which he sells.
Russian Foreign Ministry spokeswoman Maria Zakharova posted a Telegram message asking whether Western human rights NGOs would keep quiet about Durov's arrest after they criticized Russia's decision to "create obstacles" to Telegram's work in Russia in 2018
Telegram allows the creation of groups with up to 200,000 members, which critics say makes it easier for users to spread disinformation and share conspiratorial, neo-Nazi, paedophile or terrorism-related content.
In the UK, the app was scrutinized for hosting far-right channels that helped orchestrate the violent riots in English cities earlier this month.
Telegram has removed some groups, but overall its system for moderating extremist and illegal content is significantly weaker than that of other social media companies and messaging apps, cybersecurity experts say. | BGNES
