Colombia's military on Monday said it killed at least one rebel of the leftist National Liberation Army (ELN) and captured four others days before peace talks are scheduled to take place.

During the operation, the army detained the head of the group's finance committee and the leader of its public order division.

"At the location, soldiers discovered war materials, explosives, communications, logistics and devices with information of interest to state security agencies," the military said in a statement.

The operation was aimed at dismantling ELN's finances and policing mechanisms used to extort resources from farmers, ranchers and transporters in areas in which they operate, Colombia's army added.

The Defense Ministry said a separate operation led to the "demobilization" of 24 ELN rebels, according to a statement published on Twitter.

Peace talks between the leftist rebels and the Colombian government are expected to take place in the Ecuadoran capital, Quito, on October 27. However, the latest uptick in military operations against the ELN could deal a blow to the peace efforts.

Earlier this month, President Juan Manuel Santos won the Nobel Peace Prize for his efforts to end a half-century of conflict between government forces and the Revolutionary Armed Forces of Colombia (FARC).

However, voters narrowly rejected the deal with FARC, casting doubts on peace with the communist guerilla group.

More than 250,000 people have been killed and 45,000 left missing since the rebel groups launched an insurgency in 1964.

ls/cmk (AFP, dpa, EFE)