RIYADH, Saudi Arabia - Two of the largest Saudi Aramco oil facilities have been set on fire by drones.

A total of 10 drones were used in the attacks.

A set of drones struck the oil giant's facility in Abqaiq, which is near Dammam in Saudi Arabia's Eastern Province just before dawn on Saturday. The Plant is considered the world's largest crude oil stabilization plant.

The second simultaneous attack hit the Khurais oil field, a ministry security spokesperson was quoted by state news agency SPA as saying.

Abqaiq is located 75 kilometers, and Khurais 280 kilometers, south west of Dhahran.

Saudi Energy Minister Prince Abdulaziz bin Salman confirmed the drone attacks have halted production at the two plants.

Yemens al-Houthi group claimed responsibility for the attacks, the groups military spokesman said on Al-Masirah TV. It was the Houthis spokesperson that confirmed the number of drones used was 10, The spokesperson said the group was intending to broaden its attacks on Saudi Arabia, which is the lead partner of a coalition fighting the al-Houthi rebels in war-ravaged Yemen.

A successful attack on Abqaiq would be akin to a massive heart attack for the oil market and global economy, Bob McNally, who runs Rapidan Energy Group and served in the U.S. National Security Council during the second Gulf War in 2003, was quoted by the Reuters Thomson news agency as saying.

The extent of damage at the oil company's facilities has not been quantified.

"Investigations are ongoing to determine the parties responsible for planning and executing these terrorist attacks," a spokesman for the coalition said.

"The Coalition continues to adopt and implement necessary procedures to deal with such terrorist threats in order to safeguard national assets, international energy security and ensure stability of world economy," spokesman Col. Turki Al-Maliki said.

The Arab League strongly condemned the attacks.

In a statement by the General Secretariat, the league termed the attacks as "serious escalations," underscoring 'its full solidarity and support to the Kingdom in all measures taken to protect its facilities against all aggressions targeting its national interests.'

The U.S. Ambassador to Saudi Arabia John Abizaid posted a condemnation on Twitter. The U.S. strongly condemns todays drone attacks against oil facilities in Abqaiq and Khurais. These attacks against critical infrastructure endanger civilians, are unacceptable, and sooner or later will result in innocent lives being lost, his statement, posted in English and in Arabic, said. The embassy has also issued a Security Alert for Americans living in Saudi Arabia.

The timing for Saudi Aramco is not good as the company is planning an IPO, possibly as early as this year.

No official comment has been made by the company at the time of writing.

(Photo credit: Cape Breton Post).