Airstrikes took out a secret hideout in Yemen housing experts belonging to the Iran Revolutionary Guard and Hezbollah, the Arab coalition said on Thursday.

The capital, Sanaa, as well as locations in the governorates of Dhamar, Saada, and Al-Jawf were hit in a wide-ranging coalition operation to weaken the Iran-backed Houthi militia.

Al-Dulaimi airbase and warehouses in Sanaa were struck by coalition forces,  Al Arabiya TV said early on Thursday, citing sources.

Hours earlier, the coalition blew up an explosive drone targeting Abha International Airport, in Saudi Arabia’s Asir province.

The Kingdom is targeted on a near daily basis by the militia in Yemen, who use explosive drones, which are scarcely effective against Saudi air defenses.

Flights were operating normally at the airport on Thursday, with no delays or cancellations reported.

A Houthi drone targeted the same airport in October, leaving four workers with minor injuries caused by falling debris.

On Wednesday, the coalition also destroyed two drones aimed at the southern Saudi city of Khamis Mushayt. The force said it had carried out 29 operations targeting the militia in Marib and Al-Bayda during the previous 24 hours, resulting in the destruction of an air defense system and the death of over 90 Houthis.

Actions against civilians by the Houthis have been condemned by the Kingdom’s leadership repeatedly, calling them tantamount to war crimes.

The Arab coalition has been supporting the internationally recognized Yemeni government regain full control of the country after the Houthis seized Sanaa in 2014.

The resource-rich governorate of Marib has seen intense fighting between the Houthis and the Yemeni government. The militia, seeking to strengthen their control of the north with an advance into the region, has sustained heavy losses without much gain.

On Wednesday, hundreds of Yemeni government troops were deployed to the central city of Marib to reinforce the soldiers and allied tribes fighting off the bloody Houthi offensive that is encroaching on the strategic location outside the city.

Video footage on social media showed a long convoy of pickups, buses, and military vehicles carrying hundreds of soldiers who were chanting, “with our souls and blood, we will redeem you, Yemen,”  while heading to Marib.

In March, Saudi Arabia announced a roadmap called the Riyadh Initiative to halt fighting in Yemen and reopen Sanaa airport, as well as continuing talks to find a solution to the conflict. The proposal was seen as a welcome step internationally, but has been rejected by Houthi leadership.

The war, which has now lasted for seven years, has cost thousands of Yemenis their lives and has forced many more to depend on humanitarian assistance.

Saudi relief agency, KSrelief, has poured billions of dollars worth of aid into Yemen and has hundreds of projects focusing on food and health.