MOSCOW >> A demonstration in Moscow against the Russian government’s effort to block the messaging app Telegram quickly morphed today into a protest against President Vladimir Putin, with thousands of participants chanting against the Kremlin’s increasingly restrictive bent.

The key demand of the rally, with the hashtag #DigitalResistance, was that the Russian internet remain free from government censorship.

“Do you believe that Putin knows about blocking Telegram?” one speaker, Sergei Smirnov, editor-in-chief of Mediazona, an online news service, asked the crowd. “Is he to blame for blocking Telegram?”

The crowd responded with a resounding “Yes!” to both questions.

“Telegram is just the first step,” Smirnov continued. “If they block Telegram, it will be worse later. They will block everything. They want to block our future and the future of our children.”

The rally comes two weeks after Roskomnadzor, the official internet watchdog, began its bumbling effort to shut down Telegram by blocking what the regulator said was some 18 million IP addresses.

The FSB, the successor agency of the KGB, went to court to obtain the order to block the app after Telegram’s inventor, Pavel V. Durov, a Russian who lives in exile, declined to provide the security agency with the means to decrypt messages. The FSB said it needed to be able to read the messages to thwart terrorist attacks.

The effort to close Telegram has knocked out countless other sites, including some of the largest, most popular Russian websites, like Yandex and Vkontakte, the Russian equivalents of Google and Facebook. Although the shutdowns were brief, those companies did not hide their pique.

“We do not consider this situation to be acceptable,” Yandex said in a statement. “The Russian market can develop only in conditions of open competition.”

The effort has provoked anger and frustration far beyond the habitual supporters of the political opposition, especially in the business sector, where the collateral damage continues to hurt the bottom line. There has been a flood of complaints on Twitter and elsewhere that the government “broke the internet.”

“A large number of people are aware of the situation and they are not OK with it,” said Nikita Likhachev, editor-in-chief of T Journal, an online publication covering internet culture, technology and politics.

With no public accountability, nobody has any real sense of the scope of the shutdown, he said.

“The whole point about the internet being broken in Russia is that we don’t know what is happening and whether it can be fixed at all,” Likhachev said.

Countless people who play online games or use specialized services and tend to be apolitical, Likhachev said, have suddenly realized how much the government can affect their daily lives.

“They have started asking questions about what is happening,” he said.

At the rally, which was peaceful, one hand-painted sign reflected that mood: “Things are so bad that even introverts are here.”

No arrests were reported.

The rally, organized by Russia’s small Libertarian Party, had an official permit — often a sign that the government knows that a broad segment of the population is angry. The roster of speakers included opposition stalwarts like Alexei Navalny, the anti-corruption activist. He led chants of “Down with the Czar!” and called on people to continue to fight censorship at the May 5 rally he has called nationwide to protest Putin’s inauguration for a fourth term.

Various speakers and demonstrators said they had never been to any public demonstration before.

Alexander Gornik, 34, a software entrepreneur, said many of the tools that his employees use for work, like Slack, Pipedrive and Tralier, were now inaccessible. To make high-quality software that can compete globally, Russia needs to be connected to the world, he said.

“This is not just about Telegram, it is an attempt to isolate the Russian segment of the internet,” Gornik said.

Despite all the attention paid to Russian hacking and other expertise on the internet, the programmers at the government regulatory agency have not been capable of handling the complicated process of shutting down an app with international reach.

Durov, who left Russia after his previous creation, Vkontakte, was wrestled away from him in 2014, generated countless additional IP addresses to thwart efforts to block Telegram. Some 13 million Russians are among its 200 million users worldwide, and many in Russia can still access the site. Durov encouraged the demonstrators from afar with a series of posts on Vkontakte.

“Russia is at a crossroads — full-scale censorship has not yet been introduced,” he wrote in one post. “If action is not taken, Russia will lose Telegram and other popular services.”

In the early afternoon, he posted again, writing: “Thousands of young and progressive people are at this moment speaking out in Moscow in defense of the internet. This is unprecedented.”

In recent months, the Putin administration, particularly the Foreign Ministry, has repeatedly accused the West of “Russophobia” for sanctions and the general sour mood toward Russia.

One rally organizer turned that accusation on its head, telling the demonstrators that it was various politicians and bureaucrats who were shutting down the internet who were really afraid of the Russian people. He began shouting the names of some of them followed by “Russophobe,” and the entire crowd chanted with him.

There was no immediate government reaction to the protest.

Many of the demonstrators carried paper airplanes, the symbol of Telegram, which whipped around above the heads of the crowd.

The turnout of many thousands was particularly notable in that Monday was the start of a weeklong holiday, when Muscovites depart the city in droves for the country or abroad. A second rally is planned for Tuesday in St. Petersburg.

Polina Oleinik, 17 and Polina Bulakh, 16, both students, said it was the first demonstration that they had ever attended.

“Young people between the ages of 15 and 30 are very upset about this,” Oleinik said. “Russia must be a democratic country free of censorship. That is why we came.”

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