Houthi drones and missiles struck four cities in southern Saudi Arabia, wounding more than 70 people and setting fire to oil installations, in what appeared to be a major expansion of the six-month-old war in the Middle East. The strikes hit a Saudi airbase and Saudi Aramco assets in three southern cities, while the United States and Iran exchanged fire elsewhere in the Gulf.

Attacks on Aramco sites

The Houthis, who control most of Yemen's populated areas including the capital, said they launched a broad operation deep into Saudi territory. They used drones and missiles to strike a Saudi airbase in the southern city of Khamis Mushait, along with Aramco assets in Abha, Najran and Jazan.

NASA satellite images showed a thick cloud of black smoke over the Jazan refinery and a column of white smoke rising from an oil distribution centre in Abha. Saudi authorities described blazes at the sites and said women and children were among the 73 people hurt. No confirmed images from the ground were available, and witnesses could not be reached in a country where media access is tightly controlled.

The number of people wounded suggested the strikes were among the biggest against Saudi Arabia since the United States and Israel went to war with Iran in February.

Oil prices move toward $100

After a month of calm in August, fighting between Iran and the United States has resumed, pushing global oil prices back toward the $100-a-barrel level reached at the war's peak.

  • Brent crude closed at its highest level since July 23.
  • West Texas Intermediate closed at its highest level since June 4.

The Houthi attacks on southwestern Saudi Arabia have the potential to worsen the war's economic impact by disrupting Middle East energy supply beyond the blockaded Strait of Hormuz. Fighting has already caused global shortages of crude oil and the fuels refined from it. Diesel fuel in the United States is now at a record average retail price, a cost that is weighing on the political standing of President Donald Trump's Republicans ahead of the November congressional elections.

US and Iran trade fire

US forces struck multiple Iranian tankers tied to the Islamic Revolutionary Guard Corps, in response to Iranian attempts to hit a US Navy warship, a US official said. The strikes marked a resumption of US attacks on Iran after a two-day pause.

Iranian media reported multiple attacks. The Tasnim news agency said a US missile struck an Iranian tanker 4 miles (6 km) from the oil hub of Kharg Island, and the state broadcaster reported that the US attacked a second oil tanker near the waters of Jask on the Gulf of Oman. The IRGC threatened to target oil tankers in Kuwaiti and Bahraini ports in response, warning crews there to evacuate, according to a statement carried by state media.

Washington fired at Iranian tankers over the weekend in retaliation for Iranian fire at US warships, in which Iran said it used new, more capable ballistic missiles. Iran's Revolutionary Guards said they had captured a US submersible near the strait; a US official told Reuters on Tuesday that an underwater military drone had malfunctioned more than a day earlier and did not carry classified sonar or radar equipment.

Yemen's own war reignites

Saudi Arabia has led an Arab coalition battling the Houthis in Yemen for more than a decade. That war had calmed in recent years, but a ceasefire has broken down, with the Houthis threatening shipping at the mouth of the Red Sea.

Saudi-backed Yemeni forces of a government based in the south have launched a multipronged offensive on Houthi-held areas, after the Houthis tried to advance on government-held positions. The government, driven from the capital by the Houthis 12 years ago, says it aims to recapture all Houthi-held territory. Houthi spokesperson Yahya Saree accused Riyadh of escalating the war by launching airstrikes on Yemen and said the Houthis would respond.

Blockades on both sides

The wider war in the Gulf has become a test of wills between the US and Iran, with each side hoping economic pressure from competing blockades will force the other to yield. The US Treasury announced new aviation-related sanctions aimed at grounding Iran's airlines. Washington is trying to increase the flow of oil to world markets by guiding ships through the Strait of Hormuz while cutting off Iran's exports with a blockade of its own.

Tehran has announced new measures to seal off the strait, saying it will soon detail a "maritime exclusion zone" extending from the perimeter of the US blockade, through the strait and into the Gulf itself. Despite US strikes that have degraded Iran's conventional forces and punished its economy, Iran's missiles and drones can still reach US military bases in the region and hit ships in the strait.