Two Colombian engineers kidnapped while working for US-based Occidental Petroleum were freed in the northeastern province of Arauca, authorities said Tuesday.
Luis Carlos Santander and Juan Alberto Rojas, both employed by contractor Gomez Cajiao, were set free in a rural area near the town of Saravena, where they had been abducted 12 days earlier.
Two other Gomez Cajiao employees grabbed along with Santander and Rojas were released by their captors within 48 hours.
The kidnapping was attributed to the National Liberation Army, or ELN, the smaller of Colombia's two major guerrilla groups.
Santander and Rojas were examined by a medical team after their release and then taken to an army garrison. Authorities are trying to establish whether the company paid ransom for the two engineers.
The abduction was the work of the ELN, according to the provincial police commander, Col. Wilson Bravo.