The first attack on Thursday targeted airport facilities, while the second damaged a Saudia Airlines plane, the authorities said.
They’re the deadliest attacks in Saudi Arabia since Riyadh launched a major military offensive against Yemen’s Iran-backed Houthis last weekend.
The strikes also represent the first confirmed attack on the Saudi national carrier since the start of the offensive.
Though the kingdom did not say who was responsible, the Houthis claim to have targeted the airport with a ballistic missile.
Among the dead was Captain Hamoud Ali Alkalthami, according to a statement from Saudia Group, the parent company of the affected airline.
A separate statement from the company said the plane was damaged on the ground, with no passengers on board. The firm later said operations had returned to normal at the airport.
Several people “of different nationalities” were also wounded in the strikes, which sent smoke billowing over the airport and led many airlines to cancel flights to the capital ahead of a major meeting of global oil chiefs.
The civil aviation authority said injuries to citizens and people of other nationalities “ranged from minor to serious”.
Explosions were subsequently heard in Yemen’s capital of Sanaa overnight into Friday.
Meanwhile, three rocket launch platforms used by the rebels to threaten regional security were destroyed, according to the Saudi-led coalition fighting the Houthis.
The airport in the Saudi capital has been repeatedly targeted in recent days.
This week, the Houthis warned global airlines “for the last time” about the possible consequences of operating in Saudi airspace.
On Wednesday, Saudi officials said three people had been killed in Houthi-claimed attacks on airports in Riyadh and Abha.
The strikes mark a significant escalation on a developing front in the Iran war, which has seen oil prices surging and instability on financial markets.
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Saudi allies, including Kuwait and Pakistan, condemned the attack on the airport.
By Friday afternoon, at least 124 flights to and from Riyadh had been cancelled, with hundreds more cancelled the previous day, according to flight-tracking site FlightAware.
The Indian Embassy later said Air India had suspended operations through to Saturday, while the Lufthansa Group said its airlines would suspend flights to Riyadh through to next Friday. Pakistan International Airlines has also suspended flights to the city.
Amid the growing hostilities, the US embassy in the UAE has warned Americans to exercise increased vigilance.
While the EU Aviation Safety Agency recommended on Friday that airlines not operate in additional sections of Saudi airspace.
Anees al-Asbahi, spokesperson for the Houthi-run health ministry, said on X that two of the overnight strikes on Sanaa by the Saudi-led coalition injured six people, including a child.
Thursday’s strikes come as Riyadh prepares to host the WPC Energy Congress on Sunday – a major meeting of oil ministers, other government officials, and oil company executives.
Donald Trump has been reluctant to widen US military involvement in the Middle East and has not ordered American forces to resume strikes against the rebels.
The Saudi offensive aims to recapture territory the Houthis took a month ago along Yemen’s Red Sea coast, which oversees the strategic Bab el Mandeb Strait.
The rebels’ presence there threatens a key alternative shipping route to the Strait of Hormuz, where Iranian attacks on ships have held back traffic.
