Eight soldiers and 19 suspected members of Al-Qaeda were killed in Yemen on Sunday, as the army launched an offensive against key outposts of the extremists, a military official said.

General Faraj al-Bahsani, governor of Hadramawt province, told AFP the army had taken control of the Mesini Valley west of Mukalla, a central site for Al-Qaeda in southeast of the country.

Mukalla was the most populated Yemeni city under direct Al-Qaeda control from 2015 to 2016, when the army and its regional military allies seized control of the port city.

Special forces trained by the United Arab Emirates -- a key member of a Saudi-led alliance fighting alongside Yemen's government forces -- over the weekend launched the offensive, codenamed "Al-Faisal", against Al-Qaeda cells in oil-rich Hadramawt province.

Two soldiers were killed on Saturday in the offensive, which targets the Mesini and Amed Valleys -- both in the vast province of Hadramawt and home to Al-Qaeda in the Arabian Peninsula (AQAP).

The two valleys are critical to control over Yemen's southeastern coastline.

More than 9,200 people have been killed in the Yemen war since 2015, when the Saudi-led coalition joined the government's fight against Iran-backed Huthi rebels.

Radical groups, including AQAP and the Islamic State group, have flourished in the chaos of the war, regularly launching attacks on government and military targets.

The United States, the only force known to operate armed drones over Yemen, has ramped up a long-running campaign against AQAP since President Donald Trump took office in 2017.