Riyadh/Sanaa, Sept. 8 -- Yemen's Iran-backed Houthi militants launched dozens of drone and missile attacks on energy facilities and other civilian infrastructure in Saudi Arabia, injuring 73 people, according to Saudi authorities.

The attacks on Tuesday targeted four cities in the country's south-west, triggering fires at oil facilities and other installations and forcing some operations to be temporarily suspended, Saudi Arabia's military and energy ministry said.

The Saudi-led coalition fighting the Houthis in Yemen said it would give a strong response to what it described as a "dangerous escalation".

The Houthis said the attacks were retaliation for dozens of recent Saudi air strikes on areas of north-western Yemen under their control...