Two people died when a Saudi Arabian reconnaissance helicopter crashed near the border with war-torn Yemen, the first fatalities of their kind reported by the kingdom since the latest flare-up in its battle against Houthi rebels.

The incident came as missiles were intercepted elsewhere in the country and air-raid alerts sounded overnight in Riyadh, where observers are waiting for the main airport to reopen after it was shuttered about a week ago following a wave of deadly attacks.

The AH-6i helicopter’s crash near the city of Najran was due to a technical fault, the Saudi-led coalition leading a campaign against the Houthis said. That disputes the Iranian-backed group’s earlier claim that it had downed a similar aircraft.

The quickfire events suggest no immediate end is in sight in Saudi Arabia’s latest confrontation with the Yemen-based Houthis, which is wreaking a heavy toll on the kingdom.

More than a dozen people have died in Saudi Arabia in recent attacks, while the kingdom has delayed a series of global events this month that were designed to bring a boost to the economy. The militants, who’ve been at war with Saudi Arabia for a decade, stepped up their attacks in October after Saudi-backed Yemeni forces launched an offensive to recapture Houthi-held areas.

About a week after Houthi strikes on Riyadh’s airport claimed more than a dozen lives, the Saudi capital has extended remote learning for schools by another seven days and the city’s financial district hasn’t yet indicated it’s safe to return to work.

The Future Investment Initiative, the flagship Saudi financial gathering due later this month, is looking at contingency measures including virtual attendance, Bloomberg has reported.

The Saudi-led coalition said it intercepted several waves of drones over Riyadh this weekend and destroyed ballistic and cruise missiles in other areas, including attempts to target the Red Sea port city of Yanbu and the Khamis Mushait border area.

The drama has brought pledges of support from some of Saudi Arabia’s allies. Egypt’s parliament is due to convene for an emergency session on Sunday, a day after President Abdel-Fattah El-Sisi urged the assembly to authorize measures to support the kingdom’s defense, should there be a Saudi request to do so.

The aim of any authorization wouldn’t be to “fight someone or attack someone,” El-Sisi said during a military graduation ceremony. “We’re talking about for defense only.”The Houthis struck the airport in Aden, the seat of Yemen’s internationally-recognized government, on Friday night, according to the state-run Saba news agency. They hit the presidential palace in the city a few days before, killing several security personnel.

Since the beginning of October, the Houthis have attacked Riyadh’s King Khalid International Airport 20 times, leaving about 17 people dead and injuring more than 300 others. The airports of Abha, Jazan, Najran and Dammam have also come under fire, while the head office of oil giant Saudi Aramco in the eastern city of Dhahran has been hit.

The war has compounded an energy-supply crunch stemming from the almost eight-month Iran war, with the Houthis targeting ships passing through the Bab el-Mandeb strait — a key oil-export corridor. Brent crude hit $110 a barrel for the first time since May on Friday as prospects for the resumption of normal flows dwindled.