For the first time, the International Criminal Court in The Hague has opened war crimes proceedings against an Islamist militant accused of leading in the destruction of historical monuments. The charges reflect a heightened global concern about the safety of antiquities across the Middle East and North Africa, including in UNESCO World Heritage sites. Islamic State and al-Qaida affiliates are increasingly launching deliberate assaults on treasured religious monuments.

That concern should be extended to Yemen, particularly its capital. The views of the Old City of Sanaa from the rooftop restaurant at the Burj Al Salam Hotel are spectacular. Mosques and minarets jostle for space in this “city within a city.” Multi-tiered buildings of compacted earth and bricks forming intricate geometric white patterns often compared to wedding cakes are crammed together along narrow streets. Small gardens add splashes of green.

Inhabited for more than 2,500 years, Sanaa’s Old City was declared a UNESCO World Heritage site in 1986. Its roughly 6,000 houses and more than 100 mosques were built before the 11th century. The structures have housed families for many generations. Yet it is all now at grave risk.

A year ago, Ansar Allah forces, also known as the Houthis, infiltrated from northern Yemen and occupied the capital. By February, they had driven out the government of President Abd Rabbuh Mansur Hadi. On March 26, a Saudi-led coalition of nine Arab countries began an air campaign against the Houthis. The United States is providing intelligence and logistical support.

The air campaign has been responsible for most of the roughly 2,100 civilian deaths from the fighting, according to the United Nations. Many airstrikes on Sanaa, on the northern Houthi stronghold of Saada and on other cities have used cluster munitions — bombs, rockets or shells containing multiple bomblets designed to explode after spreading out over a wide area. The weapons indiscriminately harm civilians in violation of the laws of war. The Houthis have also committed abuses, including indiscriminate rocket attacks.

Houthis have been moving into Sanaa’s Old City since 2011. Stationing troops or storing weapons there could subject the site to military attacks. More recently, Yemeni loyalist forces, backed by troops from the United Arab Emirates and Saudi Arabia, have been advancing on the strategically important city of Marib, 170 km east of Sanaa, which some scholars believe is the capital of the biblical kingdom Sheba. This could become the base for a ground attack on Sanaa.

UNESCO, the United Nations cultural organization, has noted the threat to the Old City, adding it to its 2015 List of World Heritage in Danger. After a June 12 explosion in the Old City that destroyed several buildings and killed five people, UNESCO’s director general, Irina Bokova, urged all parties to protect Yemen’s cultural heritage.

“I am profoundly distressed by the loss of human lives as well as by the damage inflicted on one of the world’s oldest jewels of Islamic urban landscape,” Bokova said. “I am shocked by the images of these magnificent, many-storeyed tower-houses and serene gardens reduced to rubble.” The coalition, meanwhile, denied that the explosion was the result of an airstrike. But on Sept. 19, a coalition airstrike did hit an Old City apartment building, reportedly killing nine members of one family.

Since the first codifications of the laws of war in the 19th century, there has been recognition that civilization’s most precious objects deserve special care and protection. The massive destruction of humanity’s cultural heritage during World War II — the abbey of Monte Casino in Italy is just one of many tragic examples — gave impetus to the drafting of the 1954 Hague Convention for the Protection of Cultural Property, now ratified by 111 countries, including Yemen.

The Hague Convention and its 1999 protocol seek to protect “property of great importance to the cultural heritage of every people” by prohibiting parties to an armed conflict from using the property for purposes likely to expose it to destruction or damage. Hostile acts may not be committed against such property unless it is being used for military purposes, and there is an imperative military necessity to do so.

The Rome Statute of the International Criminal Court makes it a war crime to deliberately attack historic monuments, among other structures, unless they are military objectives.

This means that the Houthis should be moving their forces away from the Old City. It also means that the coalition forces need to take the Hague Convention protections into account if they decide to attack any Houthi forces there.

International law alone could not stop the Saudi coalition from attacking Sanaa’s Old City if Houthi military forces are deployed there. The U.S. and other coalition backers, including Britain, need to make clear their concern for this impending threat to Yemen’s — and humanity’s — cultural heritage.

The views from atop the Burj Al Salam should not become just a memory.

Belkis Wille is the Yemen researcher at Human Rights Watch. James Ross is its legal and policy director.