The Committee to Protect Journalists (CPJ) launched its annual Free The Press campaign on April 2, seeking to raise awareness about Azimjan Askarov, who is imprisoned in Kyrgyzstan, and four other "intrepid" reporters behind bars in other countries.
"Supporters are encouraged to send physical or digital postcards so that the journalists know they are not forgotten and the governments jailing them know that the world is watching," the New York-based media watchdog said on its website.
This year, CPJ's campaign highlights five journalists it says have been jailed for their work in Kyrgyzstan, Egypt, Turkey, the Republic of Congo, and China.
"These intrepid journalists come from different backgrounds and covered a variety of beats, but they were all jailed simply for doing their job," said CPJ Advocacy Director Courtney Radsch.
Askarov, a contributor to independent news websites and rights activist, is serving a life sentence in prison in Kyrgyzstan.
An ethnic Uzbek, he was convicted of "creating a threat to civil peace and stability in society" following ethnic clashes in southern Kyrgyzstan in 2010 in which more than 400 people were killed.
The case, which the jailed activist says is politically motivated, has sparked international criticism.
In December, CPJ found 262 journalists behind bars around the world in relation to their work, the highest number since the nongovernmental organization started keeping records in the early 1990s.