At least 29 Yemeni civilians have been killed after a Saudi-led air strike "decimated" a busy market in the impoverished north of the country, witnesses and rebel media say.

Local residents told Al Jazeera the raid targeted the Alaf market in the northern province of Saada shortly after midnight on Wednesday, killing 29 men and wounding at least nine others as they slept.

Rescue workers were continuing to search for seven missing people late into the evening, but videos from the scene showed the area completely destroyed by the attack with fires still burning from the charred frames of the shops.

The bodies of the victims, many of their faces disfigured beyond recognition, were laid out on white body bags for families to identify in the courtyard of a hospital morgue.

Anything that moves is at the threat of being bombed. Nowhere is safe from these criminals. Abdulrahman, local resident

Al Masirah, a TV channel run by the Houthis - a group of rebels who control Saada province, the capital Sanaa, as well as other parts of central Yemen - confirmed the death toll.

Abdulrahman, who declined to give his surname, said there were no Houthi fighters in the area when the attack happened.

"The air strike completely decimated the market," he told Al Jazeera.

"Because of repeated air strikes and mortar fire from the Saudi border, many Yemeni workers have resorted to sleeping in their shops as it's too dangerous to be on the roads at night.

"Anything that moves is at the threat of being bombed," he added. "Nowhere is safe from these criminals."

A spokesman for the Saudi-led coalition did not respond to Al Jazeera's request for comment.

Saada, a Houthi stronghold, has been repeatedly targeted by Saudi-led aerial bombardment since a coalition of Arab states joined the war in March 2015.

"We are deeply saddened to hear of the reports coming from Saada today and our UN partners are verifying the incident," Shabia Mantoo, a spokesperson for the UN's refugee agency in Yemen (UNHCR), told Al Jazeera.

"With the conflict prolonging in Yemen, we are seeing hostilities intensify, humanitarian needs accumulate and civilians bearing the brunt."

The war in Yemen, the Arab region's poorest country, started in 2014 after Houthi fighters seized control of Sanaa and began pushing south towards the country's third-biggest city, Aden.

Concerned by the rise of the Houthis, believed to be backed by regional rival Iran, Saudi Arabia and a coalition of Sunni Arab states launched an intervention in 2015 in the form of a massive air campaign aimed at reinstalling President Adb-Rabbu Mansour Hadi's government.

According to the United Nations, the number of air raids per month is now three times higher than last year, and monthly reports of armed clashes are up 50 percent.

More than 10,000 people have been killed and at least 40,000 wounded, mostly from Saudi-led air strikes.

The Saudi-led air campaign and subsequent land, air and naval blockade have created a humanitarian disaster. Cholera is on the rise and nearly 70 percent of the population is dependent on aid.

"A peaceful political solution is required more than ever to protect civilian life and to mitigate suffering," Mantoo said.

Follow Al Jazeera's Faisal Edroos on Twitter: @FaisalEdroos