Forces aligned with Yemen’s government on Thursday said that they had intercepted a drone headed towards Medina in Saudi Arabia, and a missile fired towards Riyadh, amid escalating fighting between them and Yemen’s Houthi group.

Fighting between the Saudi-backed Yemeni government forces and Iran-aligned Houthi rebels has intensified along the country’s western Red Sea coast, along with expanding Houthi attacks on oil facilities and airports in neighbouring Saudi Arabia.

On Wednesday, Yahya Saree, the military spokesman for the Houthis, also known as Ansar Allah or Supporters of God, said the group’s forces had conducted “a high-quality military operation targeting Aramco in Dhahran”, as well as strikes on Riyadh airport and a refinery in the capital.

He added that operations “will continue in the coming days, targeting Saudi enemy airports and oil facilities”.

A Saudi Ministry of Energy official confirmed that a building belonging to Aramco in Dhahran was hit, resulting in a “limited fire” but “no casualties or fatalities”. Dhahran is home to Aramco’s headquarters, a vast complex comprising numerous buildings and residential compounds.

Meanwhile, the Saudi-led coalition launched strikes against the Houthi stronghold in the Yemeni capital, Sanaa, which the armed group seized in 2014 and has held ever since. The coalition fought the Houthis, who also seized large quantities of Yemen’s military assets, until a ceasefire was agreed in 2022. That ceasefire has broken down in recent months.

Reporting from Sanaa, Al Jazeera’s Yousef Mawry said the war has become a tit-for-tat exchange of blows. The Iran-backed group “will continue to launch these air strikes and … its goal is to meet fire with fire – air strike for air strike, capital for capital, airport for airport, and energy facility for energy facility”.

Which sites have the Houthis targeted in Saudi Arabia?

Recent Houthi strikes on Saudi Arabia have mainly targeted key infrastructure on the outskirts of Riyadh, but they appear to be edging closer to the city centre.

Houthi attacks on Riyadh’s King Khalid international airport over the weekend killed 14 people and wounded more than 300 others. Houthi attacks have also been reported on other airports, including Abha international airport in southern Saudi Arabia, where two people were killed, and on Saudi Aramco energy facilities.

Authorities say Riyadh airport will remain shut at least until Saturday as several airlines cancelled flights, emptying the skies over the kingdom’s capital.

Al Jazeera’s Mawry said Saudi Arabia “has much more to lose” from tit-for-tat attacks disrupting air traffic, as Sanaa international airport has been closed for many years due to the damage it has sustained over the years of civil war. There are currently no Yemeni airliners at the airport.

Additionally, by disrupting security, the Houthis are signalling that Saudi Arabia will suffer mounting economic costs for its involvement in Yemen. Earlier this year, the Houthis similarly began launching strikes on Saudi-linked shipping in and around the Bab al-Mandeb strait at the entrance to the Red Sea. Saudi Arabia has increasingly relied on this shipping route for oil exports since Iran closed the Strait of Hormuz in March, under fire from the United States and Israel.

The kingdom is set to host a major investment conference in Riyadh later this month, dubbed “Davos in the desert”, but it is now unclear whether the event will go ahead amid the attacks.

Organisers of the Six Kings Slam tennis tournament, originally slated to begin next week in Riyadh, have announced the event will be pushed to December.

Saudi Arabia is also preparing to host the FIFA World Cup in 2034.

Al Jazeera’s Zein Basravi, reporting from the Qatari capital, Doha, said, “These military hits by the Houthi forces are meant to create a pressure campaign that is also having knock-on economic effects.”

“The Gulf Cooperation Council has become a place where these enormous events have been playing out over the past year, and if they carry on, the international implications for the global economy will continue to be negative,” he added.

What’s the situation on the ground in Yemen?

Yemeni government forces are currently engaged in a major counteroffensive operation, called “Dawn of Yemen“, to retake coastal territory seized in recent weeks by the Houthis near the Bab al-Mandeb strait, a vital maritime trade chokepoint.

The Saudi cabinet pledged in a meeting led by Crown Prince Mohammed bin Salman this week that it “will not allow its security or freedom of navigation in the Red Sea and Bab al-Mandeb strait to be threatened”.

On Wednesday, Yemeni government forces said they had carried out 2,309 “targeting operations” against the Houthis as part of their “Dawn of Yemen” military campaign.

The forces’ spokesperson, Majeed al-Nuzaili, said the operations were conducted using combat aircraft, drones, artillery and rocket launchers, and destroyed 460 Houthi military vehicles.

Government forces say they have retaken areas in Sabr al-Mawadim and al-Sarari in Taiz governorate and have repelled a large Houthi attack west of Taiz city in southwest Yemen, a government-held city that was besieged by Houthi fighters earlier this month. Taiz governorate includes the flat, western coastal region on the Red Sea, which contains the port city of Mocha and the Bab al-Mandeb. Much of the governorate also lies within Yemen’s highlands while its capital, Taiz, is nestled between mountains.

Al Jazeera’s Mawry said fighting has been so intense in the area because of its strategic value. “Whoever controls the altitude and gains control of the mountains controls the landscape. They control the Red Sea coastlines and even the city of Taiz,” he said.

The internationally recognised Yemeni government has been calling for more reinforcements as well as Saudi air attacks on the positions recently taken over by the Houthis, mainly in the district of al-Misrakh, south of Taiz, and the district of at-Turbah, which are the gateways to the city of Taiz.

Mawry reported that while the Saudi-led coalition’s aerial strikes are forcing the Houthis to withdraw and retreat, allowing government forces to advance, they have not been able to gain a full hold over some of those positions.

“It is then followed by another counter-military offensive by the Ansar Allah group to retake the area. And this is sort of the routine that we have been seeing since early September,” he said.

The Houthi siege of Taiz has resulted in civilian casualties and severe shortages of fuel, gas and other supplies. On Wednesday, the United Nations World Food Programme (WFP) reported that wheat flour stocks have been nearly exhausted.

The Red Cross said front-line hospitals in areas including Marib, Taiz and Yemen’s Red Sea coast ⁠are registering unprecedented numbers of weapon-wounded patients, with some facilities admitting more than ⁠700 casualties in a single week.