Tribal forces in Yemen's eastern Hadramawt province have taken over two army bases and plan to retake the provincial capital Mukalla from suspected al-Qaida fighters, army sources said on Saturday.
The sources said a tribal alliance took control of the bases in Shihr and Riyan, which lie on the Arabian Sea coast northeast of Mukalla, after the army withdrew on Friday.
It was not immediately clear why government troops abandoned Shihr and Riyan, nor why they pulled out of Mukalla after offering relatively light resistance. But their withdrawal highlighted the further collapse of any central authority in Yemen.
That security vacuum may give al-Qaida in the Arabian Peninsula (AQAP), a powerful regional wing of the global jihadi movement, opportunities to entrench itself further in country's remote eastern reaches.
The United States, which has carried out covert drone strikes on suspected al-Qaida targets in Yemen, withdrew its personnel from the country last month after Houthi fighters pushed south towards the al-Anad military base used by the Americans, 60 kilometers north of Aden.
Fighting continues in Aden
The Shi'ite Houthi forces, which seized the capital Sana'a six months ago along with soldiers loyal to former president Ali Abdullah Saleh, are fighting supporters of the current president in the southern port city of Aden.
Saudi Arabia and regional Sunni Muslim allies have waged 10 days of air strikes against the Houthis to try to stem their advances and to support President Abd-Rabbu Mansour Hadi, who fled Aden for Saudi Arabia more than a week ago.
In a statement, the tribal alliance said it intended to advance on Mukalla and restore security after suspected al-Qaida fighters drove out the army and ransacked the town, burning buildings and breaking into banks and the main prison.
"The leadership of the tribal alliance of Hadramawt ... calls on tribes to mobilize towards Mukalla to keep the peace and stability in Mukalla and other towns in the province," the statement said.
Town of Mukulla targeted
Witnesses and tribal sources said armed men were gathering outside Mukalla, and were waiting for reinforcements before advancing on the town itself.
Suspected al-Qaida fighters stormed Mukalla's prison on Thursday, freeing 150 detainees including a prominent local al-Qaida leader, Khaled Batarfi, Yemeni officials said.
They also broke into banks and set fire to the television broadcasting building, residents said.