The new military rulers of Myanmar on Friday ordered mobile operators and internet service providers to block access to Twitter and Instagram in the country until "further notice," Norwegian telecom Telenor said.
The government had already ordered internet providers on Thursday to block Facebook, which counts half of the population of 54 million as users, until Feb. 7.
The Ministry of Communications and Information Technology did not immediately answer a request for comment, but said previously it had blocked Facebook for the sake of "stability."
Twitter, which is also facing pressure from authorities in India, did not immediately answer requests for comment.
A spokesman for Facebook confirmed the block on Instagram. "We urge authorities to restore connectivity so that people in Myanmar can communicate with family and friends and access important information," he told Reuters.
In a statement, Telenor expressed "grave concern" about the directive and said it had challenged its necessity to authorities.
Since the ban on Facebook, thousands in Myanmar have flocked to Twitter and Instagram to express their opposition to Monday's takeover by the army and the ousting and arrest of elected leader Aung San Suu Kyi.
Many people are using social media and pro-democracy hashtags to criticize the armyΓÇÖs takeover and call for peaceful protests until the result of NovemberΓÇÖs election, which was won in a landslide by Suu KyiΓÇÖs party, is respected.
The hashtags #RespectOurVotes, #HearTheVoiceofMyanmar, and #SaveMyanmar all had hundreds of thousands of interactions by Friday, according to hashtag tracker BrandMentions.
The military has made unsubstantiated claims that the election of Suu Kyi and her National Democracy League was fraudulent. The election commission said the vote was fair.