Colombia's FARC says to declare 30-day ceasefire from December 15 HAVANA (Reuters) - Colombia's main leftist guerrilla group, the FARC, said on Sunday it would implement a 30-day ceasefire from December 15 while the government said it would keep pursuing the rebels after they attacked a police station a day earlier, killing eight. The Colombian government and the FARC are holding peace talks in Cuba aimed at ending a five-decade guerrilla war the FARC, and its smaller counterpart, the ELN, have led against the government. The conflict has killed more than 200,000 people. "We proceed to order of our guerrilla units and militias a cessation of fire and hostilities for 30 days from 00:00 hours of December 15," said Pablo Catatumbo, a FARC negotiator for the peace talks taking place in Havana. He said the group declared the ceasefire in response to strong public demand, without specifying what he meant. The FARC claimed responsibility for an attack with explosives on a remote police station in the south of the country on Saturday that killed eight people and reduced the building to rubble. The assault on the police station has caught the public's attention more than the guerrillas' regular attacks on military patrols in rural areas because it was carried out in the middle of a small town with two civilians among the dead. President Juan Manuel Santos, speaking late on Saturday from Inza, the town where the attack took place, said the government would not consider suspending its military pursuit of the FARC. "If the FARC believe that with acts like this they are going to lead us to a ceasefire, which is also what they are saying, they are totally mistaken," he said, adding that the government would consider a ceasefire only when a peace deal has been reached. We will continue attacking them. The offensive will continue," said Santos who has announced he will run for re-election in a presidential ballot next May, the campaigns for which are likely to focus on how to deal with the FARC. Though the government is in talks with the FARC, it has never agreed to a ceasefire to maintain military pressure on the group while they negotiate. The FARC is still carrying out attacks against the military and on oil pipelines. Though it is still a formidable fighting force, the FARC's numbers have been roughly halved in the last decade by a U.S.-backed military offensive. Reporting by Nelson Acosta; Writing by Peter Murphy; Editing by Eric Beech and Christopher Wilson