A suspected Saudi-led coalition air strike has killed at least 26 people in rebel-held northern Yemen, medics and local officials say.
Warplanes are reported to have bombed a hotel and a busy market in the Sahar district of Saada province.
Rebel-controlled media said the area was crowded with civilians at the time.
The coalition, which has backed Yemen's government in a two-and-a-half year war with the Houthi movement, said it was following the reports with concern.
Its Joint Forces Command will carry out a comprehensive review of operations in the area, according to a statement carried by the official Saudi Press Agency.
The coalition also stressed it was "morally and legally committed to protecting civilians as well as civilian objects" and that operations were "conducted according to the highest standard measures of targeting".
Rights groups say it has bombed schools, hospitals, markets and residential areas.
The rebel-controlled Saba news agency said the hotel and market in Sahar were crowded with workers and stall owners when the area was hit early on Wednesday.
The blast left a crater, levelled the hotel and reduced the stalls to heaps of metal.
Medics told the Reuters news agency that at least 26 people were killed, while AFP cited rebel health authorities as putting the death toll at 29.
One photograph showed the charred bodies of at least 15 male victims laid on plastic sheets in the courtyard of the local hospital's mortuary.
Another featured a man pulling the body of a boy from a wrecked building.
Last month, the Saudi-led coalition was included on a United Nations list of parties that kill and maim children in armed conflict.
The text said the coalition's actions resulted in 683 child casualties during 2016, and accused it of carrying out 38 attacks on schools and hospitals.
Yemeni pro-government forces, the Houthis and al-Qaeda in the Arabia Peninsula (AQAP) were also named on the list.
More than 8,670 people, 60% of them civilians, have been killed and 49,900 injured in air strikes and fighting on the ground since March 2015, according to the UN.
The conflict has also left 20.7 million people in need of humanitarian assistance, created the world's largest food security emergency, and led to a cholera outbreak that is believed to have affected 884,000 people and caused 2,184 deaths.