Drone attacks claimed by Yemen's Houthi rebels caused major fires at two of Saudi Aramco's critical oil facilities, the kingdom's Interior Ministry said Saturday.

Read more: Iran-US tensions flare in the Persian Gulf: What's at stake?

In a statement carried by the official Saudi Press Agency, the Interior Ministry said fires broke out Saturday at 4 a.m. local time in Abqaiq and Khurais in the kingdom's oil-rich Eastern Province as a result of "drones."

"The two fires have been controlled," the ministry said.

Abqaiq is the location of the world's largest oil processing plant, which handles two-thirds of Saudi oil production. It has a crude oil processing capacity of over 7 million barrels a day, according to the US Energy Information Administration. Khurais contains the country's second-largest oil field, with a production capacity of about 1.45 million barrels a day.

The drones triggered multiple explosions, forcing state-owned Aramco to temporarily suspend production at the two facilities, interrupting about half of the company's total output, Energy Minister Prince Abdulaziz bin Salman said. That would mean a cut of nearly 5 million barrels a day of crude production, amounting to some 5% of the global oil supply.

The explosions also led to a production halt of an estimated 2 billion cubic feet of gas per day, Prince Abdulaziz said.

Aramco CEO Amin Nasser said work was underway to restore production and a progress update would be provided in the next two days.

Escalating attacks

On the Houthis' Al-Masirah satellite news channel, military spokesman Yahia Sarie said the Iran-aligned rebels had launched 10 drones in a coordinated attack on the oil facilities in response to the Saudi-led war against rebel areas in Yemen.

In recent months, Houthi rebels have ratcheted up attacks on Saudi air bases and other facilities, hitting targets deep inside the kingdom and overcoming its air defenses.

The attacks underscore how Saudi infrastructure, including oil installations, are increasingly vulnerable to the Houthis' steadily advancing weaponry — from ballistic missiles to unmanned drones.

The conflict in Yemen is widely seen in the region as a proxy war between Sunni Muslim Saudi Arabia and its Shiite regional rival, Iran.

Western powers accuse Iran of providing the Houthis with training and equipment to launch rocket and drone attacks, something Tehran denies.

US President Donald Trump on Saturday condemned the drone attacks. "The United States strongly condemns today's attack on critical energy infrastructure. Violent actions against civilian areas and infrastructure vital to the global economy only deepen conflict and mistrust," the White House said in a statement following a phone call between Trump and Saudi Crown Prince Mohammed bin Salman.

Trump offered Prince Mohammed "his support for Saudi Arabia's self-defense," the White House said, following an earlier statement from Riyadh saying the crown prince told Trump the kingdom was ""willing and able" to respond to the attacks.

US Secretary of State Mike Pompeo condemned Iran following the attacks, saying: "Iran has now launched an unprecedented attack on the world's energy supply."

"There is no evidence the attacks came from Yemen," Pompeo said on Twitter. "We call on all nations to publicly and unequivocally condemn Iran's attacks. The United States will work with our partners and allies to ensure that energy markets remain well supplied and Iran is held accountable for its aggression."

Smoke is seen rising from the Aramco oil processing facility in Abqaiq

Growing tensions

Tensions in the Persian Gulf have skyrocketed since May, when the United States demanded buyers of Iranian oil stop purchases or face sanctions as part of Washington's "maximum pressure" campaign on Iran following President Donald Trump's withdrawal from the 2015 nuclear accord last year.

Iran responded by saying that if it could not export oil, then neither could any other country in the region.

Riyadh and Washington have blamed Iran for a series of attacks on oil tankers in the Gulf, and in June Iran downed a US drone.

sri,cw/rc (AFP, AP, Reuters)

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