Drones struck one of Saudi Arabia’s oil pipelines Tuesday as other assaults targeted energy infrastructure elsewhere in the country, and Yemen’s rebels claimed responsibility for the attacks.

The assaults marked the latest escalation of tensions in the Mideast after the apparent sabotage of oil tankers off the coast of the United Arab Emirates earlier this week and tensions spiked between the US and Iran.

Yemen’s Houthi rebels, whom Saudi Arabia has been fighting against since March 2015, said they launched a series of drone attacks on Saudi Arabia, across the border from Yemen.

The rebels’ spokesman, Mohammed Abdel-Salam, told The AP: “This is a message to Saudi Arabia, stop your aggression. Our goal is to respond to the crimes they are committing everyday against the Yemeni people.”

In a statement carried on the state-run Saudi Press Agency, Energy Minister Khalid al-Falih said that drones attacked a petroleum pumping station supplying a pipeline running from its oil-rich Eastern Province to the Yanbu Port on the Red Sea.

A fire broke out and firefighters later brought it under control, though the state-run Saudi Aramco stopped pumping oil through the pipeline.

The kingdom’s state security body also said two petroleum pumping stations in the greater region of Riyadh, the landlocked capital, were targeted at the same time.

The statement described it as a “limited targeting” of petroleum stations in areas al-Duadmi and Afif in the Riyadh region, without elaborating.

The attack on Saudi oil targets comes after four oil tankers anchored in the Mideast were damaged by what Gulf officials described as sabotage, though satellite images obtained by The Associated Press on Tuesday showed no major visible damage to the vessels.

Tensions in the region have risen since Trump withdrew America from the 2015 nuclear deal between Iran and world powers, and restored US sanctions that have pushed Iran’s economy into crisis.

Last week, Iran warned it would begin enriching uranium at higher levels in 60 days if world powers failed to negotiate new terms for the deal.

Yemen plunged into civil war in 2014 when Iran-backed rebels captured the capital, Sanaa.

A Saudi-led coalition entered the war in March 2015 to help government troops facing the Houthi advance.

The US supported the coalition for years despite its airstrikes killing civilians, and is only recently beginning to step back after the October killing of Washington Post columnist Jamal Khashoggi at the Saudi Consulate in Istanbul by Saudi agents.

With AP