Houthi rebels have seized several islands in the Red Sea and the Bab al-Mandeb Strait, strengthening their control over the key shipping route.

Axar.az reports, citing the Financial Times, that the Iran-backed group captured Perim Island, which divides the Bab al-Mandeb Strait, as well as Zuqar and Hanish islands. The advances came after the Houthis captured the port of Mocha on Yemen’s western coast on Thursday.

The offensive has also affected energy markets, with Brent crude trading below $105 a barrel on Friday after briefly approaching $110.

Saudi Arabia has launched more than 100 air strikes on areas under Houthi control, while the rebels have stepped up attacks on Saudi energy infrastructure.