Colombian troops killed 11 dissidents of the disbanded FARC guerrilla group, officials said Monday, as a fight looms over the future of a 2016 peace agreement in runoff presidential elections.

The military operation took place Sunday in the south of the country as Colombians voted in the first round of presidential elections that left a hardline conservative and a former leftist guerrilla vying for the presidency.

Defense Minister Luis Carlos Villegas said the operation in Montanita in the southern department of Caqueta left”11 dead and two wounded, including a minor who had been recruited by force.”

The 13 were part of an armed faction commanded by a former FARC rebel leader, Rodrigo Cadete, who rejected the 2016 peace agreement with the government of President Juan Manuel Santos.

The minister said the groups had been making threats against the mayor of the Caqueta capital of Florencia as well as an energy company in the region.

“The criminals had been demanding extortion payments from businesses”in Florencia and its surrounding area, the army said in a statement. Under the peace accord, the Revolutionary Armed Forces of Colombia (FARC) disarmed its 7,000 fighters in order to join the political process. It is now a political party.