In the two years since Colombia signed a peace deal with the left-wing FARC rebels, 85 members of the armed-group-turned-political-party have been killed, the United Nations said.

Colombia's special investigation unit, quoted in a new UN report published on Monday, blamed "illegal armed groups and criminal organisations" for the killings.

180917163054749

In his quarterly report on the UN's mission to Colombia, Secretary-General Antonio Guterres urged Colombia's President Ivan Duque - a vocal critic of the peace accord, signed by his predecessor Juan Manuel Santos - to better protect ex-combatants.

The FARC, formerly known as The Revolutionary Armed Forces of Colombia, now operates as a political party under the name, Revolutionary Alternative Common Force.

It has hit out repeatedly at the lack of security guarantees for its members, many of whom are struggling to reintegrate into society despite being offered amnesty in the peace deal.

Guterres said 14 ex-members of the FARC had been killed between September 26 and December 26 alone.

171002065629390

Most of the cases have been linked to the Gulf Clan drug-trafficking group that emerged out of disarmed right-wing paramilitaries in 2006, as well as FARC dissidents, the remnants of the now-disbanded EPL Marxist rebels and members of the still-active ELN armed group.

Colombia has been wracked by more than half a century of armed conflict between rebel fighters, drug-traffickers, paramilitaries and state forces, which has left some eight million people dead, disappeared or displaced.

Activists under pressure

Guterres said he was also "hugely" concerned by the number of murders of social leaders and human rights defenders in Colombia, saying the UN had verified 163 of 454 reported cases since the peace accord was signed.

"Most of the murders were in zones abandoned by former FARC [fighters] and where there is limited state presence," the report said.

Colombia's human rights ombudsman estimates that 423 activists were murdered between 2016 and the end of November last year.

180723073240153

Since the peal deal, illegal armed groups have filled the vacuum left by the FARC in isolated regions of the country.

Despite the ongoing violence, Colombia has seen a 40 percent decline in its murder rate since the deal was signed, according to the UN, with some 7,000 former FARC fighters laying down their weapons.

Colombia's peace and reconciliation commission estimates that some 1,600 dissident rebels remain active. Some FARC members refused the peace deal and continue their fight against the government and drug-trafficking activities, while other groups, including most prominently the ELN, have botched several attempts to reach a deal with the government.