In response to the unyielding situation, Italy called for reinforcements from their other colonies, notably Eritrea. With their arrival at the closing of 1926, the Italians began to move into the interior where they had not been able to venture since their first seizure of the coastal towns. Their attempt to capture Dharoor Valley was resisted and ended in failure. De Vecchi had to reassess his plans as he was being partially humiliated on some fronts. After one year of exerting full force, he could not yet manage to gain a total result over the sultanate. In spite of the fact that the Italian navy sealed the sultanate's main coastal entrance, they could not succeed in stopping them from receiving arms and ammunition through it. It was only early 1927 when they finally succeeded in shutting the northern coast of the sultanate, thus cutting arms and ammunition supplies for the Majeerteen. By this time, the balance had tilted to the Italians' side, and in January 1927 they began to attack with a massive force, capturing Iskushuban, at the heart of the Majeerteen. Hersi Boqor unsuccessfully attacked and challenged the Italians at Iskushuban. To demoralize the resistance, ships were ordered to target and bombard the sultanate's coastal towns and villages. In the interior the Italian troops confiscated livestock. By the end of the 1927 the Italians had taken control of all the sultanate. Defeated, Hersi Boqor and his top staff were forced to retreat to Ethiopia in order to rebuild the forces. However, they had an epidemic of cholera which frustrated all attempts to recover his force. By November 1927, the forces of Sultan Osman Mahamuud of the Majeerteen Sultanate were also defeated. The Dubats colonial troops and the Zaptié gendarmerie were extensively used by De Vecchi during these military campaigns. From 5 April 1908 to 5 May 1936, the Royal Corps of Somali Colonial Troops ("Regio corpo truppe coloniali della Somalia Italiana"), originally called the "Guard Corps of Benadir", served as the territory's formal military corps. At the start of its establishment, the force had 2,600 Italian officers. Between 1911 and 1912, over 1,000 Somalis from Mogadishu served as combat units along with Eritrean and Italian soldiers in the Italo-Turkish War. Most of the troops stationed never returned home until they were transferred back to Italian Somaliland in preparation for the invasion of Ethiopia in 1935.