Updated

Airstrikes by the Saudi-led coalition targeting rebels in Yemen have destroyed a small hospital run by Doctors Without Borders in the northern province of Saada, although there were no deaths and only one injury, the aid group said Tuesday.

The first of several strikes came around 11 p.m. on Monday and hit a building housing the facility's administration offices, according to Hassan Boucenine, the aid group's head of mission in Yemen who spoke to The Associated Press by telephone from the southern port city of Aden.

No one was inside at the time, he said, adding that by the time a second strike targeted the main nearby building about 10 minutes later, its occupants — some 12 staff and patients — had been evacuated.

"This attack is another illustration of a complete disregard for civilians in Yemen, where bombings have become a daily routine," Boucenine said later in a statement by the group, also known by its French acronym MSF.

It urged coalition forces to explain the circumstances around the attack, saying that the hospital's GPS coordinates were regularly shared with the Saudi-led coalition and its roof was clearly identified with its logo. The bombing of civilians and hospitals is a violation of international humanitarian law, it added.

The group operates in eight Yemeni governorates at a time when many foreign aid groups and even United Nations personnel have been evacuated. In its statement, it said the destroyed hospital had treated roughly 3,400 patients were since MSF began supporting it in May.

The Saudi-led, U.S.-backed coalition has been launching airstrikes against Yemen's Shiite rebels, also known as Houthis, and their allies since March. Saada, the Houthis stronghold, has faced a particularly intense bombardment.

The United Nations said the facility was the 39th health center hit since the violence escalated in March, adding that critical shortages of fuel, medication, electricity and water could mean many more will close. Amnesty International said the strike may amount to a war crime and called for an independent investigation.

The strike was second attack this month on the international medical charity.

On Oct. 3, U.S. gunships bombed an MSF hospital in the Afghan city of Kunduz, killing 30 people. The main building there was destroyed and the hospital has since been shut down. U.S. forces in Afghanistan said the hospital was bombed by mistake after Afghan forces requested an air strike, and President Barack Obama apologized.

Yemen has been embroiled in fighting between the Houthis and allied army units against forces loyal to the internationally recognized government as well as southern separatists and other militants.

The conflict gained international attention when the Houthis took over the capital, Sanaa, in September last year, and escalated in March when the coalition started launching airstrikes against Houthi positions.

In Geneva, the office for the U.N. high commissioner for human rights said Tuesday that some 2,615 civilians have been killed in Yemen violence over the last six months. OHCHR spokesman Rupert Colville said about two-thirds of those deaths were caused by air strikes, and the rest by Houthi rebels and their allies.

Meanwhile in the central city of Taiz, Yemen's third largest and besieged by Houthi rebels, independent security officials and witnesses said that at least 11 people were killed and 33 wounded overnight — including women, children and the elderly — when rebel shelling hit residential areas.

MSF said Houthi forces are preventing their trucks carrying essential medical supplies from entering Taiz.