Abu Dhabi-trained Giants Brigade fighters say "hundreds were killed and wounded on both sides" before Houthi rebels were allegedly expelled from a key district south of energy-producing Marib region.
Yemen's Houthi rebels have been expelled from a key battleground district by UAE-trained Giants Brigade fighters, the militia claimed, a day after the insurgents' latest missile attack on Abu Dhabi.
The Iran-backed Houthis lost Harib district south of Marib, the government's last northern stronghold which they have been fighting to seize for months.
The Giants Brigade said "hundreds were killed and wounded on both sides" in battles that lasted for more than two weeks and also secured the neighbouring governorate of Shabwa. There was no immediate comment from the Houthis.
"We thank the Arab coalition for their support for our operations in Shabwa, which were crowned with complete success," the Giants Brigade said in a statement, referring to a Saudi-led military alliance.
Prison deaths below 100
The clashes are part of a major escalation in the seven-year war after the Houthis, following a series of territorial defeats, launched a deadly drone-and-missile attack on the UAE last week.
The Saudi-led pro-government coalition that includes the UAE hit back with a series of air strikes, one of which killed at least three children and plunged Yemen into a four-day internet outage.
Internet services were restored early on Tuesday, a web monitor and AFP news agency correspondents said.
In rebel-held Saada last Friday, an attack on a prison left nearly 90 people dead and wounded more than 100, according to Doctors Without Borders.
The coalition denied being behind the prison attack, which the Houthis said had killed 91 people and injured more than 200, as they lined up the bodies covered in white sheets along the ground on Tuesday.
On Monday, the rebels renewed their attack on Abu Dhabi when two ballistic missiles were intercepted over the city, scattering debris.
The UAE, which pulled most of its troops out of Yemen in 2019 but maintains support and training for pro-government forces, warned of a "thorough and comprehensive response" to the cross-border attack.
UN officials on Tuesday said they were "alarmed by the escalating spiral of violence in Yemen that continues to harm civilians and is spilling over its borders".
The prison attack is "the worst civilian-casualty incident in Yemen in three years", the UN's special envoy for Yemen Hans Grundberg and its humanitarian coordinator for the country David Gressly said in a joint statement.
Thousands of civilian deaths
Rights groups have long criticised the coalition for civilian casualties in its aerial bombardments.
According to the Yemen Data Project, an independent tracker, there have been almost 9,000 civilian casualties from coalition air raids since 2015.
More than 150,000 people have been directly killed by fighting and millions displaced in the impoverished country, according to the United Nations which calls it the world's worst humanitarian crisis.