The Houthis, who swept across Yemen and overthrew the internationally recognized government of President Abdu Rabbu Mansour Hadi in 2015, hold the capital, Sana, and much of northern Yemen, where most of the country’s 25 million people live.
Saudi Arabia has accused Iran of backing the Houthis with weapons and expertise, and the kingdom has led an international coalition that includes the United States in fighting the rebels.
The conflict began more than three years ago, leaving more than 10,000 people dead, displacing three million more and creating the world’s largest humanitarian crisis, with millions on the brink of famine. Much of the country’s infrastructure and health system has been destroyed.
In December, the United States said it had “undeniable” evidence that Tehran was violating international law. Nikki R. Haley, the United States ambassador to the United Nations, showed off missile parts to cameras at a military base near Washington, saying they were from weapons supplied by Iran and launched by the Houthis toward the Riyadh airport.
Iran, which has long denied arming the rebels in Yemen, dismissed it as a “fake and fabricated” claim.
Military analysts at IHS Jane’s have written that the Houthis’ emerging use of ballistic missiles offers some support for American, Saudi and Israeli allegations that Iran is aiding the rebels with parts or technology, but add that it would be difficult for Iran to ship whole missiles to Yemen.
The Saudi-led coalition has often responded to Houthi missiles with a barrage of airstrikes in Yemen, though there were no immediate reports of attacks on Friday.