MOSCOW (Reuters) - Telegram, the most popular messaging app used in Russia, suffered a temporary outage on Tuesday as security services conducted stress tests on online resources to eliminate possible vulnerabilities, a lawmaker said.
President Vladimir Putin, Russia's paramount leader for over 20 years, is expected to easily win another six-year term in power at next month's election.
Telegram and other sites were affected, while some previously blocked social media apps including Instagram and Facebook suddenly became available in Russia.
The monitoring centre for Russia's public communications network said on Tuesday its specialists had recorded a "massive failure" of Telegram, without providing a reason. Telegram did not reply to a request for comment.
"The work of Telegram messenger and a number of other services in Russia is already being restored," Russia's digital ministry said in a statement, adding that there had also been failures of the app outside Russia.
"We are working to establish the cause of the incident," it said. "As for Russian telecom operators, their networks are operating normally."
But Andrei Svintsov, a deputy head of the State Duma parliamentary committee on information policy told gazeta.ru that the outages were due to pre-election work.
"These outages are due to the fact that on the eve of the presidential election, our special services are checking the operability of all systems inside Russia related to the internet and cybersecurity infrastructure," gazeta.ru quoted Svintsov as saying.
"Banned sites, banned resources, banned social networks will have access restricted once again," Svintsov added.
Reuters correspondents in Moscow noted outages of Telegram, YouTube and Vkontakte for around 90 minutes.
Soon after the outage, several previously blocked social media apps including Instagram and Facebook suddenly became available in Russia on Tuesday, according to Reuters reporters in Moscow.
Reuters reporters were able to browse Instagram without requiring a virtual private network (VPN) for the first time since blocks were imposed shortly after Russia sent tens of thousands of troops into Ukraine in February 2022.
Communications regulator Roskomnadzor has moved to block some foreign tech companies including Meta Platforms' (META.O) Facebook and Instagram.
Moscow has long sought to improve its domestic internet infrastructure, or Runet, even disconnecting itself from the global internet for tests.
Anton Gorelkin, another member of the same parliamentary committee as Svintsov, said it was unclear what had caused the Telegram outages, but that immediately blaming the Russian state was a mistake, noting "conspiracy theories" that Russia was trying to block foreign resources prior to the election.
"There have been, and will be, such incidents for a variety of reasons: from human error to hacker attack," he said.
"Much more important is how long it takes to eliminate the failure; the scale of damage to the Russian economy depends on this."