SANAA, Yemen -- Saudi-led coalition warplanes bombed Shiite rebel positions Wednesday across Yemen as a missile strike on a dairy factory killed 35 workers, authorities said, as both sides disputed who fired on it.
Wednesday's strikes marked a week of airstrikes by the Saudi-led campaign, which aims to weaken the Shiite rebels known as Houthis and forces allied with them, largely fighters loyal to Yemen's deposed leader Ali Abdullah Saleh.
Since their advance began last year, the Houthis have overrun Yemen's capital, Sanaa, and several provinces, forcing President Abed Rabbo Mansour Hadi to flee the country.
In a surprise attack, al-Qaida militants stormed the centre of the city of al-Mukalla, the capital of the southeastern province of Hadramawt, still controlled by pro-Hadi forces.
The militants assaulted the central prison in the city, with rocket propelled grenades, and freed an unknown number of prisoners, local residents and a security official said. The official, speaking on condition of anonymity because he was not authorized to speak to reporters, said it is not clear if Khalid Batarfi, an al-Qaida operative arrested over a year ago, was among those freed.
The crumbling of Hadi's government has been a concern for is a blow to Washington's counterterrorism strategy against al-Qaida's branch in Yemen, considered to be the most powerful in the terrorist network. Before the airstrikes, about 100 U.S. military advisers withdrew from the al-Annad air base where they had been leading a drone campaign against al-Qaida in the Arabian Peninsula, or AQAP.
The official said the militants proceeded to attack the branch of the Yemeni central bank in al-Mukalla, and clashes were ongoing, the official said.
The presence of al-Qaida militants in Yemen only adds to the explosive mix in Yemen, particularly as they have emerged as a powerful force against the rebels.
Wednesday's airstrikes targeted rebel-controlled army camps in the Red Sea port city of Hodeida and anti-aircraft guns there returned fire. In the firefight, missiles hit warehouses belonging to a factory that makes dairy products.
Parts of the dairy's main building collapsed with workers still inside, five eyewitnesses and officials said. At least 35 workers died in the collapse, many of them crushed to death or burned alive, according to the medical centre in Hodeida.
The coalition blamed the Houthis for the attack, while Houthi-run media blamed the coalition.
Ahmed Asiri, the coalition spokesman, denied his warplanes caused the factory collapse. He said Houthi rebels and allied fighters launched missiles at it aiming to hit civilians out "of desperation from realizing results on the ground and because they have become now isolated inside cities."
"They have targeted the diary factory. The information we got from the ground is that mortars and ... rockets hit the factory and caused the death," Asiri said.
Two Yemeni military officials loyal to Hadi said the factory had been used as a rebel weapons cache, and that while the airstrikes flattened the warehouses, the main factory building was only partially destroyed - suggesting it might have been hit from ground. Witnesses spoke on condition of anonymity out of fear of reprisals while officials spoke anonymously as they weren't authorized to speak to journalists.
A Houthi spokesman, Mohammed Abdul Salam, later said that the coalition only struck civilians in its attacks, without elaborating.
The Hodeida factory deaths came a day after international aid groups expressed alarm over high civilian casualties in Yemen's escalating crisis.
A report Tuesday by the U.N. children's agency, UNICEF, said 62 children were killed and 30 wounded during the fighting in Yemen over the past week. It was not clear if the deaths were the result of airstrikes or ongoing clashes between rival groups across the country.
Also Tuesday, the U.N. human rights office in Geneva said its staffers in Yemen confirmed that at least 19 civilians died when airstrikes hit a refugee camp near the Houthi stronghold of Saada in northern Yemen on Sunday, with at least 35 wounded, including 11 children.
Asiri called on aid agencies to co-ordinate with the coalition and concerned authorities to ensure access to areas.
"The circumstances on the ground now necessitate that we find the appropriate environment for aid agencies to be present on the ground" and to ensure that the aid reaches the needy, he said.
Critics of the Houthis charge that they are an Iranian proxy - a claim the rebels deny. Iran has provided aid to the rebels, but both Tehran and the Houthis deny it has armed them.
In Tehran, dozens of Yemeni expatriates, including clerics and students, took to the streets on Wednesday to denounce the airstrikes. The protesters burned photos of Saudi King Salman and marched outside the Saudi Embassy.
