Oil prices were on track to post weekly gains of more than 8% on Friday as attacks on tankers and energy facilities in the Middle East raised concerns over prolonged supply disruptions.

International benchmark Brent crude futures for November delivery traded at $104.09 per barrel at 3 p.m. local time (1200 GMT) on Friday, up 8.1% from last Friday’s close of $96.28, The Caspian Post reports, citing Anadolu Agency.

US benchmark West Texas Intermediate (WTI) crude futures for October delivery stood at $99.20 per barrel, representing an increase of around 8.4% from $91.48 a week earlier.

Oil prices climbed this week as renewed tensions between the US and Iran heightened concerns over shipments through the Strait of Hormuz.

Prices also received support after seven OPEC+ countries decided to keep their October production targets unchanged following approval of a combined production increase of 188,000 barrels per day for September.

Supply concerns intensified after Saudi Arabia’s Energy Ministry reported attacks on energy facilities in the country’s south on Tuesday, with fires breaking out in some areas.

Iranian officials also issued fresh warnings during the week, further raising tensions in the region.