 Complete the following phrase:  When Abu Bakr Al-Siddiq assumed the caliphate, he faced the wars of apostasy. The residents of Dumat al-Jandal and the nearby Arabs were of the apostates. In the 12th year of Hijrah, Khalid bin Al-Walid went to them after the Battle of Ayn al-Tamr. When his news reached Al Akkidar bin Abdul Malik and Al Judi bin Rabia, and they were leaders of the people, they differed. Al-Akkider saw the forces of the Muslim army, and he left Dumat al-Jandal, and Khalid bin Al-Walid sent to him who killed him. Muslims surrounded the city from two sides. The first was led by Khalid bin Al-Walid. The second was led by Ayadh bin Ghanem. The people of Dumat al-Jandal, were led by Al-Judi bin Rabia, and the Arabs were divided into two parts. Dumat al-Jandal and the Arabs army were defeated, the leaders were captivated, and the Arabs fleeded with the rest of the army to the fortress and closed it. Khalid bin Al-Walid remained in Dumat al-Jandal until he defeated its residents and uprooted the door of the fortress, then returned to Al-Hirah.32 Later, the Jawf region was not mentioned except in brief references such as it that Imru Al Qais bin Al Asbagh Al Kalbi has been the ruler of the region during the era of Umar bin Al Khattab until the 