Protection Cluster in Yemen, led by UNHCR, did not identify any party responsible

Aid agencies said last week Yemen suffered more air raids in first half of year than all 2016

An air attack on a hotel near the Yemeni capital, Sanaa, has killed at least 35 people, according to a local medic.

Physician Ali al-Rakmi who was helping at the site of Wednesday's strike in Arhab town's Qaa al-Qaidhi district, said there were more than 100 people inside at the time of the attack, all farmers who work in growing qat - a plant widely used for a stimulant effect.

At least 35 bodies were retrieved so far, he said.

Fahd Marhab, head of the Umrah hospital about 10km from the site, said there were no wounded and that all the people in the hotel were killed in the air raid.

Almaseera, a television channel run by the country's Houthi rebels, who control Sanaa, blamed the Saudi-led military coalition allied with the Yemeni government for the attack on Wednesday.

It said 41 civilians were killed and that the death toll was expected to rise further.

Officials and witnesses told the Associated Press news agency that the death toll had reached 60 and that the majority of those killed were Houthis rebels.

Reuters news agency reported that a spokesman for the Saudi-led coalition was not immediately available.

Hakim Al Masmari, a journalist with the Yemen Post, told Al Jazeera from Sanaa that air raids hit several areas of the city.

"It is probably the biggest massacre Yemen has witnessed by the Saudi-led coalition," Al Masmari told Al Jazeera by phone.

"The air strike targeted a motel late early this morning. It was part of at least 25 air strikes that targeted Sanaa and the outskirts of the city since midnight. The air strikes attacked every part of Sanaa. It was a deadly night," he added.

More than 10,000 people have been killed and three million displaced from their homes since February 2014, according to the UN.

The UN could not confirm Wednesday's attack, but rights officials were investigating the reports, according to the spokesman of UN Secretary General Antonio Guterres.

"What is clear is that any attack on civilians is unacceptable. This is a message we have often repeated and we will continue to repeat," Stephane Dujarric said in New York.

Stephen O'Brien, the UN humanitarian chief, called the conflict between the Saudi-backed Yemeni government and the Houthis a "deplorable, avoidable, completely man-made catastrophe" in a briefing to the UN Security Council last week.

The number of air strikes per month is now three times higher than last year and monthly reports of armed clashes are up 50 per cent, he said, adding that only the Saudi coalition has the means to carry out aerial attacks.

Yemen, which is on the southern edge of the Arabian Peninsula, has been engulfed in war since September 2014, when Houthi Shia rebels swept into the capital and overthrew President Abd-Rabbu Mansour Hadi's internationally recognised government.

In March 2015, the Saudi-led coalition began a campaign against Houthi forces allied with overthrown President Ali Abdullah Saleh in support of Hadi's government.

Since then, the Iranian-backed Houthis have been dislodged from most of the south, but remain in control of Sanaa and much of the north.