Turkey, Iran, and China accounted for more than half of the over 200 journalists still imprisoned worldwide as of December 1, making 2013 the second worst year on record for journalists being jailed for their work.
Governments primarily used anti-state charges, including treason and terrorism-related offenses, to silence 211 critical reporters, bloggers, and editors from around the world, the US-based Committee to Protect Journalists (CPJ) found in its 2013 census, released on Wednesday.
Other charges levied against journalists included defamation, censorship violations, ethnic or religious insults, and retaliatory charges, CPJ said.
Over half of the journalists jailed in 2013 worked for web-based publications, while 79 worked in print, and 28 others were in radio and television. About one-third of imprisoned journalists were freelancers, while the rest held staff positions.
In Turkey, the number of jailed journalists dropped from 49 last year to 40 in 2013, as some were released pending trial under new legislation.
Widely-applied anti-terror laws and penal code statutes allow the government in Ankara "to conflate the coverage of banned groups with membership", CPJ found.
Turkey is still holding dozens of Kurdish journalists on terror-related charges, and others that are accused of involvement in plots to overthrow the government.
"From the failure to reform its legislation in a meaningful way to the crackdown on its journalists in the aftermath of the Gezi Park protests, Turkey has grown increasingly repressive despite the modest decline in the number of media workers behind bars," Nina Ognianova, CPJ Europe and Central Asia programme Coordinator, stated.
The number of jailed journalists in Iran dropped to 35 from 45 last year, but journalists were still being sentenced to lengthy prison terms. In China, 32 journalists - the same number as last year - were behind bars, after a crackdown on Internet criticism was launched by Chinese authorities in August.
Eritrea, Vietnam, Syria, Azerbaijan, Ethiopia, Egypt, and Uzbekistan rounded out the top ten list of the world's worst jailers, CPJ stated, while the number of journalists behind bars rose in Ethiopia, Bahrain, Somalia, and Vietnam.
The number of journalists imprisoned in Syria dropped in 2013, but the CPJ census didn't account for those who were kidnapped or believed to be held by opposition groups. Some 30 journalists were missing in Syria as of late 2013, CPJ said.
Five journalists were still held in Egypt, compared to none in 2012, after the country's military-backed government cracked down on dozens of local and international media workers following the overthrow of former President Mohamed Morsi last July.
In Africa, Eritrea remained the continent's worst jailer of journalists, with 22 imprisoned. Eritrean detainees have never been charged with a crime or brought for trial.
Only one journalist was behind bars in the Americas: independent US blogger Roger Shuler was imprisoned for contempt of court in the US state of Alabama after he refused to comply with an injuction on defamatory content.