The Colombian army said they had killed 14 FARC rebels in Arauca, near the border with Venezuela.
The military operation involved aerial bombardments and ground troops.
(SOUNDBITE) (Spanish) ARMY COMMANDER JUAN PABLO RODRIGUEZ SAYING:
"These strikes have a major strategic impact on decreasing the capabilities of these criminal terrorists in the department of Arauca, and also on decreasing the command and control of these structures."
The latest military strike comes as the FARC and the Colombian government are negotiating in Havana, for a deal that will end a decades-long conflict that has killed more than 200,000 people.
A ceasefire expired on January 15.