At least 13 guerrillas were killed during an operation by Colombian security forces against the FARC rebels in Chigorodo, a town in the northwestern province of Antioquia.

Colombian President Juan Manuel Santos announced the operation and casualty count on Twitter, saying: "13 guerrillas are out of action in operation against Front 5 of the FARC in Chirogodo."

The Colombian air force announced in a communique that the operation staged on Monday morning along with the National Police was aimed at attacking a rebel camp "that later was neutralized by combat aircraft."

Among the dead are seven men and six women, all evidently FARC members, and security forces found a shotgun and 12 rifles along with documents that they turned over to military intelligence for analysis.

The communique also stated that a female guerrilla known as "Mayerli" and thought to be second-in-command of the FARC's Front 5 was wounded in the assault.

According to the information provided by the military, Mayerli was involved in the killing of 19 soldiers in 2009 near the rural town of Mutata.

Although the FARC and the government last October began negotiating to end the internal armed conflict that has lasted for half a century and the guerrillas declared a 2-month unilateral cease fire around the Christmas season, a recent study by the CERAC conflict analysis center found that the rebels have staged 13 attacks since the cease fire went into effect. EFE