(Fuente: BBC News)
Police General Gustavo Moreno said the bomb had been placed on a narrow dirt path and was set off remotely when a car carrying the officers drove past.
He said officers had later intercepted radio communications in which the Gulf Clan boasted about the attack.
Colombia's security forces have arrested or killed some of the top leaders of the gang in recent months, but it remains a powerful force and has reportedly also been recruiting both left-wing former Farc rebels disgruntled with the peace process as well as their right-wing former paramilitary rivals.