Strikes began on Saturday with the aim of punishing Iran-backed armed group for attacks on Red Sea shipping

US officials have said airstrikes launched against Yemen’s Iran-backed Houthis will continue indefinitely, after a first round on Saturday killed at least 31 people and injured up to 100 more.

The strikes, which aim to punish the Houthis for their attacks against Red Sea shipping, are Donald Trump’s first such use of US military might in the region since he took power in January.