Air strikes carried out by the Saudi-led coalition have hit a small hotel near Yemen's capital Sanaa, killing dozens of Shiite Houthi rebels and civilians, Yemeni security officials said.
They said an estimated number of 60 were killed in the strikes on Wednesday morning.
It was not immediately clear why the coalition jets targeted the hotel, which is located in Arhab, some 35 kilometres (22 miles) north of Sanaa.
Witnesses said the two-floor hotel in the Qaa al-Qaidhi neighbourhood was completely toppled and bodies are still being retrieved from under the rubble.
They also said another air strike hit a checkpoint manned by the Houthis, a few kilometres from the hotel.
Footage of the area aired on al-Masirah TV, a Houthi-run satellite news network, showed bodies hanging out of a simple building.
Bystanders wrapped mangled corpses into blankets to try to carry them away.
The website of al-Masirah said 41 people were killed in Arhab, describing the victims as civilians and saying the death toll was expected to rise further.
It was not possible to reconcile the different number of fatalities reported by the officials and the TV.
There was no immediate comment from the coalition.
The Saudi-led coalition has been waging an extensive air campaign against the Houthis and forces loyal to ousted Yemeni president Ali Abdullah Saleh since March 2015, seeking to push the rebels from lands they captured, including Sanaa, and restore the internationally recognised government of President Abed Rabbo Mansour Hadi to power.
But the air strikes have also hit civilian targets, such as schools, hospitals, and markets, killing thousands and prompting rights groups to accuse the Saudi-led coalition of committing war crimes.
Activists have also called upon Western countries, including the United States and Britain, to cease military support for the coalition.
Yemen's conflict began after the Houthis swept into Sanaa in 2014 and overthrew Mr Hadi's government, forcing it to relocate to the southern port city of Aden and prompting Mr Hadi to seek military support from Arab Gulf countries, led by Saudi Arabia.
The conflict has so far killed over 10,000 civilians, displaced three million people and pushed the impoverished nation to the brink of famine.
Wednesday's hotel bombing comes amid stepped-up air strikes in and around Sanaa, with army compounds and other Houthi locations targeted.
Also hit was the Rimah Hamid military camp south of Sanaa, where officers are loyal to Mr Saleh's forces.
The Houthi-Saleh alliance, meanwhile, has seen a long-simmering power struggle burst into the open.
Over the past days, the two sides have exchanged accusations and threats ahead of a rally on Thursday to mark the 35th anniversary of the founding of Mr Saleh's party, the General People's Congress.
Sanaa is packed with armed men and armoured vehicles, fuelling fears of open clashes between Mr Saleh's forces and the Houthis.
Mr Saleh has complained that the rebels have sidelined him and his loyalists, leaving them out of military and political decisions, as well as UN-sponsored negotiations to end Yemen's civil war.