"A few years back [common criminals] were taking professionals and selling them to the guerrillas, who forced them to work for them like slaves," Mora claims. "They took engineers, doctors and nurses," said Mora, who believes that his son -- a systems engineer -- was a victim of this criminal scheme.

Mora is not 100% certain of what happened to his son, but as the Colombian government prepares to continue peace talks with the FARC guerillas in Havana on November 15th, Mora will be one of hundreds of war victims pressing the rebels to disclose the whereabouts of missing Colombian citizens.

"We have never opposed the peace process, we actually support it" Mora said in a phone interview. "So long as there is transparency, on what has happened with the victims, [of Colombia's conflict]." added Mora, who runs an association for families who have kidnapped relatives, called "Los Que Faltan" or Those Who are Missing.

There is little doubt that over the past two decades, Colombia's FARC rebels have kidnapped hundreds of civilians and asked for ransom payments in order to finance their operations.

Fundacion Pais Libre, a human rights group, reports that the rebels kidnapped 2,678 civilians from 2002 to 2011. More than 400 of these victims are still in captivity or have gone missing according to that group.

But in September, FARC commander Mauricio Jaramillo shocked Colombia's human rights community by announcing that the rebels no longer held any captives. Jaramillo made this statement during a press conference in which the guerrillas announced their intent to enter peace negotiations with the government.

Peace negotiations began in Oslo Norway on October 17th, with declarations by both sides on what they were seeking to achieve through this process. The talks are set to continue in Havana Cuba on November 15th, where both sides will get into the nitty gritty of issues like how to develop Colombia's countryside and how to secure the FARC's participation in Colombian politics.

Throughout this process, the FARC have continued to refuse that they are holding any captives. In a recent statement the rebel group wrote that this was an "irrelevant" issue that should not derail the peace process, or distract participants from talking about the main issue at stake, which was how "state terrorism has been the essential cause," of violence in Colombia.

Such declarations have riled human rights groups into action, prompting them to hold multiple meetings in which victims are encouraged to provide evidence of crimes committed by the rebel group.

On October 14th for example, Pais Libre and three more groups organized a national meeting of FARC victims. In booths set up in Bogota's main square, these groups collected more than 300 complaints against the guerrilla group, filed by people who claimed that the rebels had kidnapped their relatives, killed them, or forced them to join their ranks.

Victims organizations are also finding ways for their voices to be heard as peace talks get underway.

Herbin Hoyos, a journalist who was kidnapped by the FARC in 1993, is raising funds to take the mothers of 32 victims to Havana. This delegation plans to confront negotiators with evidence of crimes committed against their sons and daughters and will also hold a press conference for journalists covering the talks.

"We don't want peace talks to advance, if there are no answers for the families of those who have been kidnapped and disappeared," Hoyos said in a phone interview, adding that victims want the government to "stand on their side."

The problem for FARC victims is that the Colombian government has also committed a large share of human rights abuses during its war with the FARC. State forces have been accused of killing thousands of peasants and of facilitating the actions of murderous paramilitary groups.

According to Chris Voelkel, a Colombia analyst at the International Crisis Group, this creates a situation where both sides have an incentive to mutually pardon each other, sweep human rights investigations under the rug, and move on to other areas of the negotiation such as rural development schemes and how to get FARC leaders to lay down their weapons.

"It would be painful for both sides to recognize that they have been murderers," Voelkel said.

But Ariel Avila, another analyst that we have spoken to about the peace talks, reckons that human rights groups within the country, and foreign governments that hand out aid to Colombia, have enough leverage over the Colombian government to stop such a deal from happening.

"Until the 1980s it was common for conflicts to end with amnesty laws," Avila said, mentioning that dictators in Brazil and Argentina stepped down in that decade, after full amnesty was granted to members of those regimes.

"International standards do not permit [such deals] any longer," Avila claimed.

In previous peace negotiations with right wing paramilitary groups, the Colombian government has implemented legal schemes that forced paramiltaries to tell the truth about actions like kidnappings and the mass execution of civilians, in exchange for reduced prison sentences.

These truth and reparation schemes have helped some victims of paramilitary groups to learn who killed their relatives, and to recover their remains from clandestine graves.

It remains to be seen if the FARC would accept such a deal, and what sort of concessions they would seek from the Colombian government, in exchange for participating in truth commissions.