12 Colombian soldiers and police killed in ambush by leftist ELN rebels

GUICAN, Colombia, Oct. 27 (UPI) -- At least 11 Colombian soldiers and a police officer were killed Monday in an ambush sprung by leftist rebels with the National Liberation Army, or ELN.

The BBC reports the attack occurred as the group left an indigenous reservation near the town of Guican, in the eastern part of Colombia's Boyacá department.

The security personnel were protecting poll workers, and the group was reportedly carrying regional election ballots. Six people, including poll workers and a local guide, remain missing.

Despite a peace agreement last month between the Colombian government and rebels with the Revolutionary Armed Forces of Colombia, or FARC, attacks by the ELN, a separate entity, have continued. Since 1964, the Marxist-Leninist group, with about 2,000 armed combatants and an unknown number of active supporters, has warred with the Colombian government.

The group reportedly killed three soldiers in the Norte de Santander department of the country last month. Colombian army commander Alberto Mejia told reporters one soldier was found "incinerated and dismembered because of the attack."

In June, the Colombian military said it killed Jose Amin Hernandez Manrique, leader of the ELN's Dario Martinez Front, during in a clash in Antioquia department. Days later, ELN rebels destroyed a Colombian military Black Hawk helicopter as it landed near a village in Norte de Santander.

Following the Monday ambush, Colombian President President Juan Manuel Santos, who reportedly said the election had been "the most peaceful and least violent in decades," promised retaliation against the ELN.