Twitter has become a popular means of expression for dissidents and activists around the world.
However, a global backlash spread against the social networking service Friday after it announced it will allow country-specific censorship of tweets that might break local laws.
The San Francisco-based company said its commitment to free speech remains firm, but many activists say the company is selling them out.
"This is very bad news," tweeted Egyptian activist Mahmoud Salem, who operates under the name Sandmonkey. Later, he wrote, "Is it safe to say that - Twitter is selling us out?"
"If Twitter censors, I'll stop tweeting," one Chinese activist tweeted in response to the news.
However, Twitter did have some defenders.
"Twitter is being pilloried for being honest about something that all Internet platforms have to wrestle with," said Cindy Cohn, legal director of the Electronic Frontier Foundation. "As long as this censorship happens in a secret way, we're all losers."
Twitter will post a censorship notice whenever a tweet is removed, and it will post the government's removal requests on the website Chilling Effects.