Yemen's armed Houthi movement said it launched ballistic missiles at "economic and vital targets" in the southern Saudi province of Jizan on Saturday - and Saudi Arabia said it intercepted an attack.
The reported launch came days after the Houthis vowed to revenge the killing of one of their top leaders, Saleh al-Samad, in a Saudi air strike last week. Thousands of his supporters massed in the streets of Yemen's capital for his funeral on Saturday.
Both sides have fought to a stalemate after more than three years of war in Yemen. A Saudi-led military coalition is trying to restore Yemen's internationally recognised government that was forced into exile after the Houthis took over large parts of the country in 2014 and seized the capital Sanaa.
The Houthi-run state news agency Saba reported that the group had fired eight missiles over the border into Saudi Arabia.
The kingdom's Arabiya TV quoted the Saudi defence ministry as saying four missiles bound for the province had been intercepted. Neither agency provided further details. Details in reports from both sides frequently differ.
Saudi and other warplanes from the mostly Gulf Arab alliance have carried out thousands of air strikes, repeatedly hitting markets, hospitals and other civilian targets, killing hundreds of civilians. The coalition says it does not target civilians.
The Houthis have fired more than 100 ballistic missiles into the kingdom, causing few casualties, but fuelling accusations by their adversaries and the United States that Iran is providing the missiles to their Houthi allies.
Tehran and the Houthis deny the accusation. The group says it is fighting for Yemen's sovereignty against a Western-backed plot to dominate the country.