The leftist Revolutionary Armed Forces of Colombia, or FARC, handed Marcos Baquero over to the International Red Cross and former Sen. Piedad Cordoba in the southeastern jungle.
He was flown on a loaned Brazilian military helicopter emblazoned with Red Cross symbols to Villavicencio, gateway to Colombia's eastern plains. Looking somber, he embraced his wife and two small children on the airport tarmac.
Baquero, who wore jeans and a white, long-sleeve shirt, did not talk to reporters. He is the 15th captive released by the FARC since early 2008 in what are widely seen as good-faith gestures seeking a peace dialogue.
Cordoba has been the go-between in all those releases, but Colombia's solicitor general stripped of her Senate seat in September and banned her from public office for 18 years for alleged collusion with the FARC.
Colombian President Juan Manuel Santos has permitted Cordoba to continue her role brokering hostage releases.
He said Monday, however, that he won't consider peace talks with the FARC until it frees all captives, halts attacks and stops drug trafficking and extortion. Santos also insists the FARC stop sowing land mines, which kill and maim hundreds of Colombians a year.
Unlike his two predecessors, Santos has yet to name a peace commissioner.
Fewer than 20 so-called political hostages remain in FARC hands though some have been held for more than 13 years.
Of the four additional captives the rebels have promised to free through this weekend, the longest-held is a police major captured in May 2007.
The FARC has been fighting a succession of Colombian governments since 1964, demanding a more equitable distribution of wealth and the dismantling of a property system in the countryside that has allowed a small, wealthy elite to violently displace several million peasants.
Colombia's government has engaged the FARC in peace talks at least three times during those years, all of which failed.
"Words aren't enough. Communiques aren't enough. We need real gestures of peace," Vice President Angelino Garzon said this week.
Santos, who was defense minister in the previous government, has launched legislative initiatives to return stolen land to peasants and compensate victims of Colombia's conflict that were positively received by the rebels' top leader, Alfonso Cano, in a New Year's video.
The FARC, whose field marshal was killed in a September air raid, has nevertheless shown no inclination to accept a cease-fire.
The editor of the communist weekly Voz, Carlos Lozano, told The Associated Press that while he's impressed by the current sober atmosphere, there must be significant trust building if peace talks are to be joined.
"There's still a lot to be done," he said. "And for that reason I don't have great expectations."
Associated Press writer Frank Bajak in Bogota, Colombia, contributed to this report.
(This version CORRECTS name of newspaper to Voz rather than La Voz.)