Global online freedom declined for a fifth consecutive year as more governments stepped up electronic surveillance and clamped down on dissidents using blogs or social media, a survey shows.
The most free among the 65 countries assessed was Iceland, followed by Estonia, Canada, Germany, Australia, the United States and Japan.
At the bottom of the list was China, worse than runners-up Syria and Iran in terms of a lack of online freedom. Cuba and Ethiopia rounded out the bottom five.
The annual report by non-government watchdog Freedom House said the setbacks were especially noticeable in the Middle East, reversing gains seen in the Arab Spring.
Freedom House found declines in online freedom of expression in 32 of the 65 countries assessed since June 2014, with "notable declines" in Libya, France and Ukraine.
The researchers found 61 percent of the world's population lives in countries where criticism of the government, military or ruling family has been subject to censorship.
And 58 percent live in countries where bloggers or others were jailed for sharing content online on political, social and religious issues, according to the "Freedom on the Net 2015" report.
In a new trend, many governments seeking to censor content from opponents have shifted their efforts to targeting online platforms, pressuring services like Google, Facebook and Twitter to remove content, the report said.
"Governments are increasingly pressuring individuals and the private sector to take down or delete offending content, as opposed to relying on blocking and filtering," said Sanja Kelly, Freedom House's project director.
"They know that average users have become more technologically savvy and are often able to circumvent state-imposed blocks."
Freedom House said governments in 14 of the 65 countries passed laws over the past year to step up electronic surveillance.
The report said online freedom took a hit in France from new restrictions on online content that could be seen as an "apology for terrorism" and from a new surveillance law.
It also noted France's "sweeping legislation requiring telecommunications carriers and providers to, among other things, install 'black boxes' that enable the government to collect and analyse metadata on their networks."
In Libya, Freedom House cited "a troubling increase in violence against bloggers, new cases of political censorship, and rising prices for Internet and mobile phone services".
In Ukraine, the report highlighted "more prosecutions for content that was critical of the government's policies, as well as increased violence from pro-Russian paramilitary groups against users who posted pro-Ukraine content in the eastern regions".
Overall, 18 countries were rated as "free" online, while 28 were classified as "partly free" and 19 "not free."