On 20 April, the South Africans captured Dessie on the main road north from Addis Ababa to Asmara, about south of Amba Alagi. In eight weeks the British had advanced from Tana to Mogadishu at a cost of 501 casualties and eight aircraft and had destroyed the bulk of the Italian air and land forces. From Debra Marqos, Wingate pursued the Italians and undertook a series of harrying actions. (In early May most of Gideon Force had to break off to provide a suitable escort for Hailie Selassie's formal entry into Addis Ababa.) By 18 May, Maraventano was dug in at Agibor, against a force of about including only soldiers ( the Frontier Battalion and the re-formed 2nd Ethiopian Battalion).