AL MUKALLA, Yemen — Saudi Arabia said its air defenses destroyed at least one ballistic missile fired late Sunday, apparently by Yemen’s Houthi rebels, as it zoomed over Riyadh, the Saudi capital.

The launching and reported destruction of the missile, which Saudi news accounts said had caused loud booms, came on the third anniversary of the Saudi-led bombing campaign against the Houthis in Yemen, the Arab world’s poorest country.

The missile attack also came as the architect of the bombing campaign, Crown Prince Mohammed bin Salman, was in the midst of a friendship visit to the United States, which has aided the Saudi military’s intervention in Yemen.

A brief report on Saudi Arabia’s state-owned Al Arabiya website said that Patriot missile batteries operated by the Saudi Air Force in Riyadh had intercepted at least one incoming missile and that witnesses had reported “loud explosions and bright flashes in the sky.”

It was not immediately clear whether any missile debris caused casualties or damage on the ground. Remains of a Houthi-fired missile fired in November barely missed a passenger terminal at Riyadh’s international airport.

Amateur videos uploaded onto YouTube appeared to show that at least one of the Patriot missiles fired on Sunday failed to hit its intended target, instead doing a U-turn and crashing with a huge flash on the ground.

The Houthis, who are supported by Saudi Arabia’s regional rival Iran, have fired missiles several times into Saudi Arabia.

The Saudis and the Americans have accused Iran of violating a United Nations arms embargo by providing military weapons and supplies to the Houthis, including missiles. Iran has denied the accusation but has defended the missile launchings, calling them a justified response to devastating Saudi-led aerial attacks in Yemen.

In their own account of the attack on Sunday, the Houthis said they had fired at least three ballistic missiles into Saudi Arabia. Assuming that account is accurate, it was not immediately clear what happened to the others.

The Houthi account, carried by the Saba news agency in Yemen, also quoted the group’s leader, Abdul Malik al-Houthi, as saying in a speech that he would remain defiant to “Saudi-American aggression.”

The Saudi intervention in Yemen, which began on March 25, 2015, has helped cause what the United Nations has called the world’s worst humanitarian disaster, exacerbated by strict Saudi controls on shipping into the country.

A majority of the Yemen population is in urgent need of food. The country has been upended by severe hunger and threats of famine, forced displacement and preventable diseases including cholera and diphtheria.

Geert Cappelaere, the Unicef director for the Middle East and North Africa, who just completed a weeklong visit to Yemen, said on Sunday that the country had one of the world’s highest number of acutely malnourished children.

“It is fair to say today that every single girl and boy in Yemen is facing acute humanitarian needs,” he said. “Three years of war, decades of chronic underdevelopment have done something for the children of Yemen — but unfortunately nothing good.”