By Jana Choukeir, Maha El Dahan, Timour Azhari and Yasmine Ghania
DUBAI/RIYADH, Oct 11 (Reuters) - Yemen's Iran-aligned Houthis claimed responsibility for Saturday's strike on Riyadh's international airport that killed 13 people and wounded more than 300, as Saudi authorities reported people were injured in a new attack on the airport on Sunday.
The Saudi-led coalition in Yemen said an "unidentified projectile" had targeted Riyadh's international airport Terminal 4 on Sunday, causing a fire. An unspecified
number of people were injured, the Saudi civil aviation authority said, adding it was still assessing the damage.
The coalition also said Saudi air defences had intercepted a cruise missile in the vicinity of King Khalid International Airport.
The strikes have exposed vulnerabilities in Saudi defence capabilities as the kingdom wages an air campaign against the Houthis to support a ground war in Yemen by the Yemeni government against the Iran-aligned group.
The airport has been closed since Saturday's attack. However, a long-planned international energy conference went ahead in Riyadh on Sunday as planned.
HOUTHIS CLAIM RESPONSIBILITY FOR OTHER ATTACKS
In a televised speech on Sunday, Houthi military spokesperson Yahya Saree claimed responsibility for Saturday's attack and also said the group had attacked the airport in Dammam in Saudi Arabia's Eastern Province and two facilities of Saudi oil giant Saudi Aramco.
There was no immediate Saudi confirmation. Reuters has reached out to the Saudi media office and to Aramco for comment.
The Houthis earlier on Sunday had renewed their warning to airlines, airport workers, and travellers against using Saudi airports.
"We urge everyone to take our warnings seriously, and Saudi Arabia bears responsibility for any failed interceptions," the group said.
'WORSE IS YET TO COME,' HOUTHIS WARN
Saudi Arabia has stepped up its military involvement in Yemen in recent weeks, launching strikes against the Houthis and backing a Yemeni government counteroffensive after the group seized strategic territory along the Red Sea coast last month.
The Houthis said on Sunday that Saudi Arabia carried out 124 air strikes in Yemen in the past 24 hours, including the capital Sanaa and the group's stronghold Saada.
Yemen's Houthi-run foreign ministry said that further Saudi military action in Yemen would trigger a stronger response, adding that its actions would be guided by the principle of reciprocity.
"Unless the Saudi enemy stops its aggression and interference in Yemen, worse is yet to come, God willing," the ministry said in statements carried by Houthi-run Al Masirah television.
US President Donald Trump said on Saturday the United States was considering joining Saudi strikes on the Houthis in the conflict, a spillover from the wider war on Iran that the US and Israel launched in February.
INTERNATIONAL ENERGY CONFERENCE STILL GOING AHEAD
The five-day conference of international energy organizations WPC Energy opened as planned on Sunday at a convention centre some 10 km (6 miles) from the airport.
Meanwhile, a ministerial meeting of the International Energy Forum also went ahead on Sunday, with its plenary session to be held behind closed doors, according to a media advisory. No further details were immediately available and it was not clear which ministers joined the meeting.
Italy's energy minister, Gilberto Pichetto Fratin, whose country was co-hosting the event, had said on Friday he would participate remotely via video link.
German officials were trying to organise a return flight for Economy Minister Katherina Reiche, who was in Riyadh to attend the WPC conference and ministers' meeting.
She was supposed to return to Berlin on Monday but the ministry said it appeared likely that her flight would not be able to take off due to the closure of the airport and alternatives were being considered.
Separately, Saudi authorities notified parents that in-person classes at all schools in Riyadh would be suspended and shifted to remote learning from Sunday until Thursday for all students, teachers and administrative staff.
In Saturday's attack, the third on Riyadh's airport in a week, the dead included four Saudis, two Bangladeshis and nationals of the United States, Jordan, Palestine, Syria, Sudan and Egypt, Saudi authorities said. India's embassy in Riyadh said on Sunday one of its citizens injured in the attack had died, adding to the initial death toll of 12.
Four people were killed in the two previous attacks on the airport earlier in the week. One of the attacks also caused heavy damage to a Saudi commercial plane parked on the tarmac.
(Reporting by Jana Choukeir and Maha El Dahan in Dubai, Timour Azhari Riyadh, Menna Alaa El-Din and Yasmine Ghania in Cairo, James Mackenize and Sarah El Safty; Editing by Andrew Mills and Gareth Jones)
