Messaging app Telegram said its CEO Pavel Durov, who was detained in France on Saturday, had “nothing to hide”.
Mr Durov He was arrested at an airport north of Paris, under a warrant for app-related crimes, according to authorities.
Mr Durov has been accused of failing to take steps to prevent criminal uses of Telegram, and the inquiry is said to have shown a lack of restraint. The app has been accused of failing to cooperate with law enforcement in drug trafficking, child sexual content and fraud.
“Its moderation is within industry standards and continues to improve,” Telegram said in a statement.
“To claim that a site or its owner is responsible for misuse of that site is absurd,” App said.
The Telegram said Mr Durov travels frequently in Europe and operates within EU laws Digital Services Act, Aimed at ensuring a safe and responsible online environment.
“Nearly one billion users worldwide use Telegram as a means of communication and a source of vital information,” the app's statement said.
“We await an immediate resolution of this situation. The telegram is with you all.”
Judicial sources quoted by the AFP news agency said Mr Duro's detention was extended on Sunday and could last up to 96 hours.
Pavel Durov, 39, was born in Russia and currently lives in Dubai, where Telegram operates. He holds dual citizenship of the United Arab Emirates and France.
Telegram is especially popular in Russia, Ukraine and former Soviet Union countries.
The app was banned in Russia in 2018 after it previously refused to hand over user data. The ban was lifted in 2021.
Telegram is ranked as one of the major social media platforms after Facebook, YouTube, WhatsApp, Instagram, TikTok and WeChat.
Mr Durov founded Telegram in 2013. He fled Russia in 2014 after refusing to comply with government demands to shut down opposition communities on his VKontakte social media site, which he sold.
On Sunday, the Russian embassy in France wrote on Facebook that it was seeking to “clarify the reasons for the detention, protect the rights of Mr Dureau and facilitate consular access”.
The post added that French officials were not cooperating with Russian authorities.
Russian Foreign Ministry spokeswoman Maria Zakharova posted on Telegram asking whether Western human rights NGOs would remain silent on Mr Duro's arrest after criticizing Russia's decision to “create obstacles” to Telegram's work in Russia in 2018.
Telegram allows groups of up to 200,000 members, which critics have argued makes it easy to spread misinformation, and users can share conspiracy, neo-Nazi, pedophilic or terrorist-related content.
In England, the app was scrutinized for providing far-right channels that were instrumental in organizing violent disorder in English cities earlier this month.
Telegram has removed some groups, but overall its system for controlling extremist and illegal content is significantly weaker than other social media companies and messenger apps, cyber security experts say.