BOGOTA: Leftist National Liberation Army rebels killed 12 security officials Monday even as the government pushes for a peace deal with the larger FARC guerrilla force, President Juan Manuel Santos said. “While we had one of the least violent election days in years (Sunday), the ELN today has slaughtered 11 army troops and a police officer in Boyaca,” Santos said in a televised address from the presidential palace. The Santos government has been engaged in peace negotiations with Colombia’s largest guerrilla group, the FARC, since 2012, which the sides aim to wrap up with a final peace deal by March 2016. The ELN has participated in preliminary peace talks with the government since 2014, but has not yet opened a formal peace process. Colombians voted in local and regional elections on Sunday.