The Telegram messaging app has been blocked in China amid accusations of allegedly aiding Chinese human-rights lawyers in their everyday work and organizing. The block follows a massive cyber attack against the company’s Asia-Pacific servers earlier this month.

Hong Kong Free Press first reported the block on July 13. According to blockedinchina.net, access to Telegram’s web-version has been blocked from servers located in Beijing, Shenzhen, Inner Mongolia, Heilongjiang and Yunnan provinces in China.

On July 12, Chinese state-run newspaper People's Daily published an article accusing Telegram of aiding human-rights lawyers and advocates, who allegedly used the app and its “Secret Chat” mode (which allows messages to self-destruct after a period of time) to engage in “attacks on the [Communist] Party and government.” These accusations are the latest in a series of attacks on human rights advocates in China, with 23 individuals already arrested, and over a 100 others facing pressure from the state. Some human rights lawyers, like Pu Zhiqiang, have also faced persecution for their messages on Chinese microblogging website Weibo.

Telegram, run by a Berlin-based non-profit, was founded by Russian Internet entrepreneur Pavel Durov, who is also the founder of Russia's biggest social network, VK (often dubbed “Russia's Facebook”). After facing pressure from the Kremlin to share personal data about the VK community organizers of Euromaidan groups and to shut down a Russian anti-corruption group, among other things, Durov sold his share of VK, was forced out of a leading role in the company, and left Russia in search of new beginnings.

On July 10, Telegram reported a massive DDoS (distributed denial of service) attack on its Asia-Pacific servers. Founder Pavel Durov wrote about the cyber attack on Twitter.

@aavst Глобальный DDoS на все датацентры Telegram. Кто-то недоволен. — Pavel Durov (@durov) July 10, 2015

A global DDoS on all Telegram data centers. Someone's unhappy.

In a blog post on its official site, Telegram speculated the attack could have been initiated by its Korean competitors, Kakao Talk and Line, whose users moved to Telegram en masse in 2014 because of censorship.

By now we know that the attack is being coordinated from East Asia. We've noticed a three-fold increase in signups from South Korea in the last two weeks. The last time we were hit by a massive DDoS was in late September, 2014, in the wake of the South Korean privacy scandal when signups from that country spiked as well. We've also heard that some companies are unhappy with our new platform that allows artists to create free custom stickers for the users. Two weeks after its launch we were hit by a lesser DDoS, also aimed specifically at the Asia Pacific cluster.

While there has been online speculation that the Chinese government could also be responsible for the DDoS attack, Telegram has not offered any official versions about the source of the attack, but did say it came from South-East Asia.

@xoclate @telegram We're on it 24 hours a day. Managed to be online for 95% of users. The attack is coming and is coordinated from SE Asia. — Pavel Durov (@durov) July 12, 2015

When asked about reports of the China block, Durov told TechCrunch that he didn't think Telegram was “completely blocked in China,” but said the traffic from the region had decreased. “[But] if we do get completely blocked in China, we’re not going to play cat and mouse with their government at this stage. Let them block,” Durov reportedly said.

Durov's native Russia has also been considering a crack-down of sorts on messenger apps like Telegram. In July, Ivan Tavrin, the president of MegaFon, Russia’s third largest telecom operator, asked the Russian government to consider introducing new regulations for the messaging services WhatsApp, Viber, and Skype. Apart from the apps being in competition with traditional SMS services offered by telecom providers, Tavrin took issue with the security of the messengers, claiming they put dangerous power in the hands of terrorists and spammers.