The Colombian military killed at least five FARC guerrillas in the northwest of the country Monday, part of a new offensive that has challenged ongoing peace talks with the rebel group.

The Colombian military killed at least five FARC guerrillas in the northwest of the country Monday, part of a new offensive that has challenged ongoing peace talks with the rebel group.

A bombing in the remote Choco department killed the fighters, military sources said, but they were unable to provide more details about the attack.

The government has intensified military operations against the Revolutionary Armed Forces of Colombia (FARC) in recent days even as bilateral peace talks continue in Havana.

So far some 40 rebels have been killed in renewed bombings after President Juan Manuel Santos' ended a government suspension of airstrikes in April following a rebel attack that killed 11 soldiers.

The FARC suspended its unilateral ceasefire policy Friday and briefly broke off the scheduled talks after a strike last week killed 26 rebels.

FARC leader Pablo Catatumbo condemned the strikes as a "step backward" as the Marxist group resumed talks in Cuba with the Colombian government Monday.

Santos rules out any ceasefire before a final peace agreement is reached, but he recently ordered that the names of rebels killed be released, breaking practice with usual government policy.

Founded in 1964, the FARC has some 8,000 fighters mostly in rural areas.

Colombia's internal conflict has killed some 220,000 people, left six million dead and dragged on for decades.