India, Sept. 9 -- The Iranian-backed Houthi rebel group in Yemen launched a wave of attacks on Saudi Arabia on Tuesday, wounding more than 70 people and igniting fires at oil facilities and utilities in the kingdom, authorities said.

The attack was a major escalation in renewed fighting between an important US ally and the Iranian proxy group. It also threatened to further destabilise a region rocked by nearly three years of wars and deliver a new blow to the global economy.

Weeks of clashes have added pressure to limited global oil supplies as the Houthis target a shipping route Saudi Arabia has used to transport oil to world markets while the Strait of Hormuz is throttled due to the US-Iran war. Tuesday's attacks hit Saudi oil facilit...