Three Colombian soldiers were killed and three injured in an attack the army said Tuesday was executed by the Gulf Clan drug trafficking gang in retaliation for the weekend arrest of its leader, “Otoniel.” The attack, carried out with explosives in northwest Colombia, was “retaliation for the capture of the most wanted drug trafficker,” Army General Juvenal Diaz told Blu Radio. He did not say when it happened. Otoniel, his real name Dairo Antonio Usuga, was arrested in the Antioquia department where the attack occurred.