Saudi Arabian air defense systems intercepted two ballistic missiles launched from Yemen toward oil refineries in Yanbu on Saturday, Greek security sources told Reuters, as Saudi Arabia and the Iran-aligned Houthis exchanged fire in an escalating front in the regional conflict.

The attack came hours after the Saudi-led coalition in Yemen said it had struck Houthi military sites in the Red Sea port city of Hodeidah on Friday, targeting facilities it said were linked to the group's attacks on commercial shipping. The Houthis have declared a naval blockade of Saudi Arabia.

Last week, Houthi leader Abdul Malik al-Houthi warned that Saudi oil infrastructure and other critical facilities would become targets for the group's missiles and drones if Riyadh deepened its involvement in the conflict.

Saudi Civil Defense, the state's emergency services agency, issued warnings for Yanbu, on the Red Sea coast, and later said the danger had passed. Civil Defense also issued a warning for the port city of Jizan, home to a 400,000-barrel-per-day oil refinery.

There were no immediate official reports of damage, and Saudi state oil giant Aramco did not immediately respond to requests for comment.