Amnesty International on Monday welcomed the release of a member of the Colombian security forces held captive for almost a year by the Revolutionary Armed Forces of Colombia (FARC).
The organization also urged the guerrilla group to put an immediate and unconditional end to kidnapping and hostage-taking.
The FARC on Sunday released army soldier Josué Daniel Calvo, held since 2009, and is soon expected to release army sergeant Pablo Emilio Moncayo, held captive by the group since 1997, and to return the remains of police officer Julián Ernesto Guevara, who died in captivity in 2006.
"The joy of the families reunited with their loved ones should not obscure the suffering of those who remain in captivity and their families, as well as of those who have had no news about the fate of family members who are missing or disappeared," said Marcelo Pollack, Amnesty International's Colombia Researcher.
Although the number of kidnappings has fallen sharply over recent years, guerrilla groups, as well as paramilitary groups and criminal gangs, continue to hold hundreds of people.