Saudi Arabia said early Friday it thwarted an attack by Yemen’s Iran-backed rebels that sparked a fire near an Aramco oil distribution center, involving unmanned boats loaded with explosives dispatched into the Red Sea.

In remarks carried by the state-run Saudi Press Agency, an unnamed official at the Ministry of Energy reported that Saudi security forces had intercepted and destroyed two explosives-packed boats that it said Yemen’s Houthi rebels were using to target a major refinery and terminal in the southern Saudi province of Jizan.

The attempted attack took place late Wednesday near an offloading platform and caused the floating hoses that unload oil to catch fire, according to the energy official, who added that the blaze had been brought under control and caused no injuries.

The official sharply condemned the attack as threatening commercial shipping routes near the vital Bab al-Mandeb strait, used for oil shipments from the Gulf to Europe, as well as goods from Asia to Europe.

There was no immediate acknowledgement from Yemen’s rebels, who have repeatedly fired drones and missiles targeting oil installations, airports and cities in the Saudi mainland over the course of a grinding five-year war against a Saudi-led military coalition. In September 2019, drone attacks claimed by the Houthis struck two key oil installations in Saudi Arabia, halting about half of the supplies from the world’s largest exporter of oil. Saudi Arabia and the US attributed the assault to Iran, which has denied involvement.

Saudi Arabia often claims to foil Houthi cross-border attacks, but evidence is scarce, making it extremely difficult to independently verify the accounts.

The Houthis, which Saudi Arabia considers to be Iranian proxies, overran Yemen’s capital and much of the north in 2014, driving the internationally recognized government into exile. The war in the Arab world’s poorest country has killed over 100,000 people, pushed millions to the brink of famine and precipitated what the UN calls the world’s worst humanitarian crisis.