Telegram, the popular encrypted messaging app, claimed that it had experienced a state actor-sized” DDoS cyber-attack last week. It has pointed to china as the probably place of origination of the attack.

The service, Reuter reported, was hit by a “powerful DDoS attack” originating from IP addresses mostly inside China, Pavel Durov, Telegram’s CEO, said in a tweet. He also added that the attack coincided with protests in Hong Kong.

Hong Kong is seeing thousands of protesters marching in opposition to a controversial law that would allow people in the city to be extradited to China. Telegram and other encrypted messaging apps are popular tools that have been used by protesters globally, to coordinate, incognito. Durov also added that historically, attacks of the same size had coincided with protests in Hong Kong, and this was not the first time this had happened. In 2014, at the height of the city’s Umbrella Movement, Beijing cut access to photo-sharing app Instagram inside the mainland. Clearly, other apps have faced blocks in China as well during political movements in Hong Kong. In 2015, there was a similar attack on the company’s service, just when China was initiating a crackdown on human rights lawyers in the country.

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At that time, a lawyer involved in human rights cases was made to confess on state television about his involvement in the “attacks on the [Communist] Party and government” and how his colleagues were using Telegram to hide messages from surveillance of Chinese authorities.

However, during that attack, Telegram’s CEO did not comment or make any allegations. However, this time around, he is making things quite clear on his social media posts.

HI Tweet reads: “IP addresses coming mostly from China.  Historically, all state actor-sized DDoS (200-400 Gb/s of junk) we experienced coincided in time with protests in Hong Kong (coordinated on @telegram). This case was not an exception.”

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The Chinese state media have sharply condemned the protests. They claim these protests are motivated by external forces and designed to disturb the social stability in Hong Kong. The country’s cyber policy centre- Cyberspace Administration of China (CAC), did not respond immediately to a faxed request for comment Reuters.

Chinese officials have previously denied allegations of cyber-attacks, claiming that China is also very frequently a victim of outside attacks.

Meanwhile the media reports are not letting chin authorities get away so easily. In an article in the Hong Kong Free Press, the situation on the mainland was described- where the company’s web version of its app was blocked from servers in Beijing, Inner Mongolia, Heilongjiang, Shenzhen and Yunnan.

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