Meanwhile, the guerrilla movement switched its main effort to the north and on 5 October 1975 guerrillas struck the 29th Mountain Infantry Regiment. The 5th Brigade suffered a major blow at the hands of "Montoneros", when over one-hundred—perhaps several hundred—Montoneros guerrillas and "milicianos" (militants) were involved in the planning and execution of the most elaborate Montoneros operation in the so-called "Dirty War", which involved the hijacking of a civilian airliner, taking over the provincial airport, attacking the 29th Infantry Regiment's barracks at Formosa province and capturing its cache of arms, and finally escaping by air. Once the operation was over, they made good their escape towards a remote area in Santa Fe province. The aircraft, a Boeing 737, eventually landed on a crop field not far from the city of Rafaela. In the aftermath, 12 soldiers and 2 policemen were killed and several wounded. The sophistication of the operation, and the getaway cars and safehouses they used to escape from the crash-landing site, suggest several hundred guerrillas and their civilian supporters were involved.