Fighters from of the Southern Transitional Council (STC) fire towards positions of Saudi-backed government forces during clashes in the southern Abyan province. — AFP/VNA PHOTO

ADEN — Fighting broke out Monday between pro-government troops and separatists in southern Yemen, leaving 10 dead, security and medical officials said, in the first major clash since separatists declared self-rule in the south.

The two sides fought for control of Zinjibar, the capital of Abyan province, the separatist Southern Transitional Council (STC) said.

Pro-government troops launched an offensive on the outskirts of Zinjibar, some 60km from the main southern city of Aden, security sources from both sides said.

An STC official, Nabil al-Hanachi, said that his forces managed to "stop the attack and kill many of them".

He said the attack was carried out by the military wing of the Islamist party Al-Islah, which is allied with the government.

Medical sources said that two government soldiers were killed and 13 wounded, while the separatists had two dead and 11 wounded.

The casualties were transported to local hospitals. AFP journalists saw a government armoured vehicles on fire near Zinjibar, as STC forces celebrated their "victory".

The fighting complicates Yemen's five-year war between the government – backed by a Saudi-led military coalition – and Iran-backed Huthi rebels who control much of the north, including the capital Sanaa.

The government and the STC have technically been allies in the long war against the Huthis.

But the separatists in the south, which used to be an independent country, have agitated to break away again – a campaign that was temporarily put to rest with a power-sharing deal signed in Riyadh last November.

On April 26, however, the STC declared self-rule in southern Yemen, accusing the government of failing to carry out its duties and of "conspiring" against their cause.

Over the past six years, the Yemen conflict has killed tens of thousands of people, mostly civilians, and triggered what the United Nations considers to be the world's worst humanitarian crisis. — AFP