We have compiled a list of similar cases in which messaging services were earlier blocked around the world.
EU Countries
To date, there is no EU legislation restricting messengers or access to user data, but in the wake of a wave of terrorist attacks in Europe in 2015-2016, there were multiple calls to introduce the relevant legislative measures.
In August 2016, following a spate of deadly attacks in Paris in November 2015 and in Nice in July 2016, French Interior Minister Bernard Cazeneuve said the European Commission should introduce a law obliging operators to cooperate in investigations of Islamist militants and terror-related crimes.
"If such legislation was adopted, this would allow us to impose obligations at the European level on non-cooperative operators," he told a joint conference with his German counterpart in Paris. Cazeneuve then touched upon Telegram, an encrypted app used worldwide, which he said did not cooperate with governments. He added that legislation should target both EU and non-EU companies.
"The fight against terrorism is the first priority for Europeans," Cazeneuve said. "It’s imperative that police have a single interface."
French intelligence chief Patrick Calvar described the Telegram app in May 2016 as "the main network used by terrorists." There were, for instance, reports that Daesh extremists who had used Telegram included a 19-year-old who attacked a Catholic church in Normandy, Northern France, in 2016 and reportedly used the app to detail his plans.
Last June, Germany passed a law that extended the authorities’ power to intercept and spy on encrypted data sent via message services such as WhatsApp and Skype.
German investigators were thus empowered to incorporate into users’ smartphones and PCs spy software (or a "Trojan horse") to access data in major encrypted messengers. First the software targeted only terror-related cases, whereas now it also focuses on money-laundering and tax evasion incidents, as well as violations of migration legislation, etc.
UK’s Home Secretary Amber Rudd is to announce a crackdown on criminals who exploit the dark web in pursuit of drug deals, child pornography, guns, credit scams and other illegal activities. Back in March 2017, in the wake of the Westminster bridge terrorist attack, she stressed terrorists could have used the encrypted WhatsApp messaging service to plan the assault. Rudd famously told the Conservative Party Conference that she doesn’t "need to know how encryption works to understand it’s helping the criminals."
In May that same year, the UK media reported on the authorities’ intention to draft a law which would oblige such messengers as Telegram and WhatsApp to take down digital protection if needed or "allow someone competent to do that."
READ MORE: Darkweb Policing Needs Global Effort: UK's Combat 'Drop in the Ocean' — Analyst
Brazil
On December 17, 2015, Brazil saw WhatsApp messenger being blocked for 48 hours after it refused to hand over information upon a court request. In the same case, on March 1, 2016, police arrested Diego Dzodan, the vice president of Facebook Latin America in Brazil (Facebook is the company that owns WhatsApp), but released him the following day. There was another “blocking” incident in May 2016, but the court’s decision was successfully appealed.
Iran
In 2014, the authorities deliberated blocking WhatsApp messenger, but it was not reportedly fulfilled upon the personal order of the country’s president, Hassan Rouhani.
On December 30, 2017, following a series of anti-government rallies, Telegram was blocked in Iran, but was again operational two weeks later.
READ MORE: Facebook CEO Zuckerberg's Messages Exclusively Deleted From Other People's Chats
China
The Chinese government has on more than one occasion declared a massive struggle for “world wide web security.”
Since the 2000s, the authorities have been blocking all widespread foreign messenging services that refuse to cooperate with the nation’s security services. Instagram, a photo-sharing service, has been blocked there since 2015, Telegram – since 2015; WhatsApp’s operations were halted in September 2017. A range of experts name among the reasons not merely an attempt to prevent violations of Chinese laws, but also the country’s policy to knock foreign telecom companies out of the domestic market.