In late 1942, at the army's instigation, SOE mounted its first operation, codenamed Operation Harling, into Greece in an attempt to disrupt the railway which was being used to move materials to the German Panzer Army Africa. A party under Colonel (later Brigadier) Eddie Myers, assisted by Christopher Woodhouse, was parachuted into Greece and discovered two guerrilla groups operating in the mountains: the pro-Communist ELAS and the republican EDES. On 25 November 1942, Myers's party blew up one of the spans of the railway viaduct at Gorgopotamos, supported by 150 Greek partisans from these two organisations who engaged Italians guarding the viaduct. This cut the railway linking Thessaloniki with Athens and Piraeus.