The U.S. technology companies “have caved into the Kremlin’s blackmail,” Leonid Volkov, a top aide to jailed opposition leader Alexey Navalny, wrote on Telegram. The Putin critic’s supporters denounced the move as “a shameful act of political censorship.” 

Democratic U.S. Senator Chris Murphy called the move “indefensible.”

Google removed the app under pressure after officials threatened to imprison its local employees, a person close to the company said, speaking on condition of anonymity. Apple and Google didn’t immediately respond to requests for comment. 

Russian authorities had accused the companies of meddling in the elections by offering the opposition apps despite court rulings banning access to the content. The head of parliament’s committee on investigating foreign interference in Russia’s domestic affairs, Vasily Piskarev, said Thursday the companies’ staff could face criminal charges if the apps weren’t removed, the state news service Tass reported. Regulators warned of new fines and other measures. 

‘Smart voting’

Navalny’s so-called smart voting initiative aims to galvanize discontent over stagnant living standards to defeat ruling party candidates. Russia is holding three days of voting for the State Duma lower house of parliament from Friday to Sunday, in which Putin’s unpopular United Russia party is counting on a commanding victory.

The smart-voting app, also accessible through Navalny’s eponymous version, wasn’t accessible Friday on Google Play or App Store in Russia, though it remains visible to users in other countries. Russian courts have banned online references to smart voting and declared Navalny’s organizations “extremist.”

Kremlin spokesman Dmitry Peskov welcomed the removals, saying, “these applications are illegal on the territory of our country.”

The crackdown also led to interruptions in access to Google Docs in Russia after Navalny’s supporters used the text editor to distribute its lists of recommended candidates, according to Roskomsvoboda, an Internet advocacy group. Similar problems were reported earlier in the week with Apple’s App Store, through which the smart voting app was distributed.

President Vladimir Putin, 68, after two decades in power has sharply stepped up efforts to rein in the internet, which has remained a bastion of free speech. Earlier this year after mass protests at Navalny’s imprisonment, Russia slowed down access to Twitter. It also slapped fines of several million dollars on social media companies including Facebook and Google for not deleting calls for demonstrations that were ruled illegal by authorities.

The Kremlin has resorted to pushing competitors off the ballot and Navalny allies have been forced into exile or jailed. The smart voting effort, which mostly urges picking Communist candidates, could still present a challenge to the Kremlin’s preferred contenders in some races, particularly in major cities.

Internet crackdown

The Foreign Ministry summoned the U.S. ambassador last week to complain that American “digital giants” are violating Russian laws on non-interference in elections. Court bailiffs visited Google’s office in Moscow early this week over the smart voting ban.

“Formal grounds already exist for the complete blocking in Russia of Apple, Google, YouTube, Twitter, Facebook and others,” said Damir Gainutdinov, an Internet freedom expert at the Agora human rights group. Authorities also trying to force virtual private network providers to stop users from circumventing bans and accessing unauthorized content, he said.

“For now, it seems they are just testing their ability to limit information,” said Gainutdinov. “But the risk is that Russia may opt for much tighter control.”

The Internet restrictions come as the Kremlin has waged an increasing crackdown on political life, detaining thousands of protesters and jailing opposition activists. Navalny, who’s serving a 2 1/2 year prison term, barely survived a chemical poisoning last year he and Western governments blamed on the Kremlin. Russian officials deny any role in the nerve-agent attack. Russia this year also banned Navalny’s organizations, labeling them extremist.