At least ten fighters were killed and 30 wounded as southern Yemeni separatists fought government troops in the southern city of Aden on Sunday, local medics said, deepening a rift between forces that had been on the same side.
The worst clashes yet between southern separatists, who are allied to the United Arab Emirates (UAE), and forces loyal to the Saudi-based government risk crippling their once united war effort against the Iran-aligned Houthi movement in Yemen's north.
Yemen has been torn apart by three years of conflict between the Saudi-backed government of President Abd-Rabbu Mansour Hadi and the Houthi, and the factional fighting in the south compounds the misery.
The fighting broke out after the expiry of a deadline imposed last week by separatists from the Southern Transitional Council (STC) for Hadi to dismiss the government of Ahmed bin Daghr, accusing it of corruption and mismanagement.
Gunmen were deployed throughout most districts of Aden on Sunday and there was heavy automatic gunfire and explosions in the southern port city, according to Reuters witnesses.
Armed separatists appeared to gain the upper hand by wresting a key military base and several government buildings from soldiers loyal to Hadi, local newspaper Aden al-Ghad reported on its website. Residents said that hundreds of pro-Southern demonstrators had gathered in a main square.
Several hospitals said at least 10 fighters were killed in the fighting and 30 others were wounded.
Bin Daghr called for a truce and instructed forces loyal to his government to return to their barracks, the government-controlled Saba news agency reported.
Bin Daghr had earlier denounced the separatists' actions as a coup and said the outcome of contest in Aden was in the hands of their backers, the UAE, who enjoy overall control in the city, and warned that the situation was headed toward "a comprehensive military confrontation ... (which is) a direct gift to the Houthis and Iran".
"This is a serious matter and the coalition and Arabs as a whole must move to save the situation," bin Daghr wrote in a message on his Facebook page. "The matter is in their hands and the hope, as we see in the government see it, is on the (United Arab) Emirates."
Recreating south Yemen
Although Hadi remains in exile in Saudi Arabia, his administration and local allies nominally control about four-fifths of Yemen's territory, but political and military leaders in Aden now want to revive the former independent state of South Yemen.
The STC last week accused Hadi's cabinet of corruption and inefficiency and demanded they quit.
A top military adviser to President Hadi, Mohammed Ali al-Miqdashi, said any move toward rebellion would render the southerners an enemy.
"There is no difference between the Houthis and anyone else who rebels against the legitimate government, no matter who they are - left, right, south, east," said Miqdashi, speaking at a remote military base near the central Yemeni city of Marib, late on Saturday.
A senior southern political source accused the government of pushing the dispute toward an armed showdown.
"The Hadi government was nervous about any demonstration by the people, so they tried to stop it by force thinking that if there were a battle, the coalition would intervene and save them," the source said.
In a statement late on Saturday before the clashes began, the Saudi-led coalition urged all parties to seek "calm and restraint, adhering to the language of a calm dialogue."
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