ADEN - Three suspected Al-Qaeda militants were killed in a clash Wednesday with forces loyal to President Abedrabbo Mansour Hadi in southern Yemen, local government sources said.

The jihadists were travelling towards the city of Aden, the government's temporary base, when loyalists manning a checkpoint in neighbouring Abyan province stopped them, sparking a gunfight, the sources said.

The three suspects were coming from the southeastern city of Mukalla, which Al-Qaeda in the Arabian Peninsula (AQAP) has controlled since April.

Yemen, home to what the United States considers Al-Qaeda's most dangerous affiliate, has been convulsed by unrest since Iran-backed Huthi rebels seized Sanaa in September 2014. The militants, including AQAP and the Islamic State group, have gained ground in and around Aden.

Al-Qaeda fighters have also seized the town of Azzan in Shabwa province east of Abyan, local officials and tribal chiefs said on Monday.

The authorities have struggled to exert control over several southern regions that loyalists have recaptured from the Huthis and their allies since July.

There has been a string of bombings and assassinations, many claimed by IS, targeting security forces and government officials.