SANAA, Yemen — An airstrike on Saturday hit a funeral hall packed with thousands of mourners in Yemen’s capital, Sanaa, and local health officials indicate that over 140 people were killed and more than 525 wounded, the U.N. humanitarian coordinator for Yemen said.

Nasser al-Argaly, the Health Ministry’s undersecretary, told a news conference earlier that the Saudi-led coalition was responsible for the airstrike, which one rescuer said turned the site into a “lake of blood.” At the time, al-Argaly said at least 82 people were killed and 534 wounded, but cautioned that the casualty figures were not final.

Jamie McGoldrick, the U.N. humanitarian coordinator in Yemen, said in a statement that the humanitarian community in the country is “shocked and outraged” by the airstrikes. He condemned the “horrific attack” and reminded all parties to the conflict “that under international humanitarian law, they are obliged to protect civilians and civilian infrastructures.” He called for an immediate investigation into the incident.

“The international community must exert pressure and influence on all parties to the conflict to ensure civilians are protected,” McGoldrick said. “This violence against civilians in Yemen must stop immediately.”

He said initial reports from health officials in Sanaa indicate that over 140 people were killed and more than 525 injured, McGoldrick said.

The incident has prompted the U.S. to initiate an immediate review of its already reduced support for the Saudi-led coalition, White House national security council spokesperson Ned Price said.

Yemeni security and medical officials said the dead and wounded include military and security officials from the ranks of the Shiite Houthi rebels fighting the internationally-recognized government of President Abed Rabbo Mansour Hadi as well as the Houthi’s allies, loyalists of President Ali Abdullah Saleh.

Among those killed was Maj-Gen. Abdul-Qader Hilal, head of the capital’s local council, according to the officials. Saturday’s funeral was held for Sheikh Ali al-Rawishan, father of Galal al-Rawishan, the interior minister in the rebel-led government. Galal Al-Rishwan was seriously wounded in the attack.

In the aftermath of the strike, hundreds of body parts were found strewn in and outside the hall. Rescuers collected them in sacks. The strike left the building little more than a shell, with most of its walls and roof gone. Cars parked outside were mangled by the blast.

“The place has been turned into a lake of blood,” said one rescuer, Murad Tawfiq.

Ambulances rushed to the site to ferry the wounded to hospitals. In radio broadcasts, the Health Ministry summoned off-duty doctors and called on residents to donate blood. Rescuers, meanwhile, sifted through the rubble in search of more casualties, but a fire that erupted hindered their work.

The international humanitarian community rushed to provide trauma kits, blood bags and medical supplies, and deployed medical staff to local hospitals, McGoldrick said.

Mohammed Abdul-Salam, the Houthis’ spokesman in Sanaa, angrily denounced the airstrike as the latest act of “genocide” by the Saudi-led coalition.

“The silence of the United Nations and the international community is the munition of the murderers,” he said. “Those murderers will not escape divine justice.”

The United States has been backing the Saudi-led coalition, but White House national security council spokesperson Ned Price said the U.S. is “deeply disturbed” by the reports on the funeral hall airstrike which “if confirmed, would continue the troubling series of attacks striking Yemeni civilians.” He warned that U.S. security cooperation with Saudi Arabia “is not a blank check.”

“In light of this and other recent incidents, we have initiated an immediate review of our already significantly reduced support to the Saudi-led coalition and are prepared to adjust our support so as to better align with U.S. principles, values and interests, including achieving an immediate and durable end to Yemen’s tragic conflict,” Price said in a statement late Saturday.

The Saudi-led coalition backs Hadi’s government which, together with its own allies, is fighting the Houthis and Saleh loyalists in a civil war that broke out in 2014.

Roughly 3,799 civilians have been killed since the Saudi-led air campaign began in March of last year, according to a recent report by the U.N.’s human rights chief, Zeid Ra’ad al-Hussein. The U.N. and rights groups estimate the conflict has claimed the lives of at least 9,000 people and displaced nearly 3 million more in the Arab world’s poorest country.

According to the report, coalition airstrikes were responsible for 60 percent of civilian deaths over a year-long span starting in July last year. Just under one-quarter — 475 — civilian deaths were attributed to rebel forces like those loyal to Saleh, and another 113 to affiliates of al-Qaida and the Islamic State group.