Iran-backed Houthi militants in Yemen say they carried out drone and ballistic missile attacks on the Saudi capital Riyadh, as well as energy sites on the country’s Red Sea coast.

Saudi authorities said they intercepted and destroyed a ballistic missile fired at Riyadh earlier that day, without confirming any further strikes or causalities.

Earlier, a column of black smoke was seen rising from fuel tanks near the Saudi capital’s international airport, where flights were disrupted temporarily on Saturday.

Air raid alerts had sounded in the capital for the first time since the Iran-backed Houthis increased their attacks on Saudi Arabia in July.

Air defences also stopped “hostile attempts to target civilians” in the cities of Bish, Taif, Farasan and Yanbu, an official spokesperson for the Saudi-led coalition said in a statement.

In a statement posted online, Houthi military spokesman Yahya al-Sarea said a “large number of ballistic and cruise missiles and drones” had been used to attack “sensitive sites” in Riyadh and Aramco state oil and gas company facilities in Yanbu on the coast.

He added that the attacks were “in response to the Saudi enemy’s criminal attempts” to target the Yemeni capital Sanaa.

Earlier, Sarea had accused Saudi Arabia of carrying out 300 strikes across Yemen during the past week.

The Houthis are locked in a civil war with Yemen’s internationally recognised government, which is backed by Saudi Arabia.

They have attacked targets inside Saudi Arabia on several occasions in recent months, and said this week that they were responsible for downing a Saudi fighter jet over Yemen.

According to an unconfirmed report from AFP news agency, quoting military sources on both sides of Yemen’s civil war, fighting between the Houthis and Saudi-backed government forces claimed 48 lives on Saturday.

The Houthis said 31 of their fighters had been killed while government sources said their side had lost 17 soldiers, according to the news agency.

On Friday, the International Organization for Migration, a UN body, reported that the number of people displaced as a result of recent fighting had passed 104,796, external.

A number of apparent explosions were heard in Riyadh and major problems were reported at King Khalid International Airport earlier on Saturday, with the tracking website FlightRadar24 reporting delays and cancellations., external

An AFP journalist reported that firefighters could be seen trying to extinguish the flames of a burnt-out fuel tank belonging to Aramco.

The Saudi Civil Defence had sent out phone alerts overnight warning of potential danger in Riyadh and other regions, before issuing an all-clear on Saturday morning.

Residents told AFP on condition of anonymity that they had heard what sounded like a round of explosions echoing through the city after the alerts.

“I heard the alarm, then my windows shook,” said a resident of northern Riyadh, 27. “It was definitely scary. I was not expecting this.”

The Houthis recently seized control of the strategic port city of Mokha and Perim Island, a gateway to a key shipping route used by the Gulf state to export to Asia and Europe.

The group said the naval blockade was in retaliation for a Saudi blockade of ports and airports in Houthi-controlled north-western Yemen.

Saudi vessels have relied on that stretch of the Red Sea for oil exports since the US and Israel’s war with Iran effectively closed the Strait of Hormuz.

On Friday, investment banking giant JP Morgan said it was struggling to predict how oil prices would be impacted by the war, telling investors in a rare note that “we simply don’t know how to model the endgame”.