At least 12 killed in Riyadh airport attack in Saudi Arabia

Twelve people were killed and at least 309 others injured in the third attack this week targeting King Khalid International Airport in the Saudi capital, Riyadh, that forced a suspension of operations, according to an official statement from the country's civil aviation authority.

Calling the assault a "fully-fledged war crime," the Saudi-led military coalition has blamed Iran-backed Houthis in neighbouring Yemen and promised a firm response.

Emergency vehicles responded to explosions as thick black smoke billowed from the complex. Sources say a missile past Saudi air defences to strike terminals 3 and 4 of Riyadh's main airport Saturday afternoon.

A flight-tracking site shows all flights to Riyadh were either diverted or cancelled.

It is the deadliest attack in the kingdom in more than a decade.

Authorities confirm the fatalities include four Saudis, two Bangladeshi nationals, and one person each from Palestine, the United States, Jordan, Syria, Sudan and Egypt.

The injured are being treated at several hospitals. Some remain in critical condition.

A projectile also landed in the vicinity of King Fahd International Airport in the eastern city of Dammam, says a spokesperson for the Saudi-led coalition.

US President Donald Trump calls the latest strike on the Riyadh airport "terrible." Asked whether he thinks the Saudis could defend themselves, Trump expresses confidence in their capabilities.

(Reporter: President, you saw the attack on Riyadh airport killed like a dozen people. What do you think about that?)

Trump says, "I think it's terrible. Well. You're going to find out, see, but I think it's terrible. Terrible...Well, they're able to defend. Look, the Saudis are good fighters. But I think the attack was a terrible thing."

Trump tells members of the media that he will soon speak to Saudi Arabia's Crown Prince Mohammed bin Salman and is weighing whether Washington will join the Saudi forces in carrying out airstrikes against Houthis amid the wider Iran war.

Also on Saturday, an American military jet struck the stern of a commercial cargo vessel, the Panama-flagged M/V Ocean Molica, in the Gulf of Oman and disabled its propulsion without harming the crew, as part of the US efforts to maintain a naval blockade of Iranian ports.

The US Central Command announces disabling four commercial vessels and turning around 135 ships from mid July.