Yemeni and Emirati troops advanced into the southern port city of Mukalla on Sunday, officials and residents said, entering a stronghold of al Qaeda's Yemeni wing for the first time in over a year of war.
Fighter jets from the mostly Gulf Arab alliance pounded the city on Sunday and killed 30 militants, residents said, as the military coalition ramped up an offensive to wrest swathes of southern Yemen from Al Qaeda in the Arabian Peninsula (AQAP).
Mukalla has been the centre of a rich mini-state that al Qaeda built up over the past year as it took control of an almost 600-km (370-mile) band of Arabian Sea coastline and pocketed customs revenues from the port.
Losing Mukalla would take away the AQAP's main source of revenue, which has enabled it to thrive for over a year, but the alliance offensive appeared too strong for it to withstand.
"The liberation of Mukalla from the hands of the al Qaeda terrorist organisation has begun," local governor Ahmed Saeed Bin Breik said in a statement.
"Al Qaeda fighters are departing," said one resident who reported that coalition armoured vehicles and armed forces had entered the city.
Local officials said clerics and tribesmen had negotiated with the militants to get them to leave Mukalla peacefully and residents said their fighters were withdrawing westward to neighbouring Shabwa province.
Dozens of armoured vehicles and hundreds of troops gathered in Ramah, around 70 km (44 miles) north of Mukalla, to prepare to move in, they added.
Sunday's air strikes on al Qaeda in Mukalla were carried out in coordination with a ground offensive in militant-controlled territory further west, a Yemeni military official said.
The push is being led by the United Arab Emirates, which has been training and arming local recruits for months, according to southern Yemeni tribal and political sources.
The UAE is part of a mostly Gulf Arab coalition that intervened in Yemen's civil war in March last year to support the internationally recognised government after it was forced into exile by the armed Houthi group, an ally of Iran.
Winning back territory
Sunday's air strikes come as Yemen's government meets with the Houthis in Kuwait to try to find a solution to the conflict.
Around 6,200 people have died in the war, which has focused mostly around the country's Houthi-controlled centre and north, while a security vacuum spread in the south.
The United States has for years used drone strikes in Yemen to target AQAP, which has plotted to place bombs on international airliners and claimed credit for the Charlie Hebdo magazine attack in Paris last year.
Fearing more air strikes, residents reported that local families were bundling into cars and driving out of town.
On Saturday, Yemeni troops battled al Qaeda at al-Koud near Zinjibar, another southern city considered an al Qaeda stronghold, while an air strike from a drone killed two suspected al Qaeda fighters south of the city of Marib.
In a statement on its official Twitter account, AQAP said it carried out a suicide bombing attack against the government troops pushing into al-Koud.
The Houthis control the capital Sanaa in the north while the Saudi-backed Yemeni government has tried to re-establish itself in the southern port city of Aden. Only in the last month has its fledgling army begun to make gains against the militants and organise to take back lost territory.