Leftist rebels killed at least 25 soldiers during separate clashes in Colombia on Saturday, the military said. Another 18 soldiers were reported missing.
The heaviest fighting took place in remote southwestern Putumayo state, one of Colombia's main cocaine-producing regions, where 19 soldiers were killed, an army spokesman said on condition of anonymity, according to government policy.
The fighting erupted after the Revolutionary Armed Forces of Colombia, or FARC, attacked an army convoy near Puerto Asis, 330 miles southwest of Bogota, the spokesman said.
Warplanes and attack helicopters were called in to strafe rebel positions, said Gen. Edgar Lesmez, Colombia's air force commander.
Separately, government troops backed by warplanes clashed with leftist rebels blocking a road in northeast Colombia, killing at least six soldiers and wounding three, said Gen. Edgar Ceballos, the local army commander.