A drone boat packed with explosives has detonated in the Red Sea.
The US navy says the vessel belonged to Houthi rebels, and no damage or casualties have been reported since the blast.
Houthis, who control much of Yemen and are aligned with Iran, have launched multiple attacks on commercial vessels in the Red Sea since November.
The group say the attacks are a protest against Israel’s military operations in Gaza.
International shipping has been severely disrupted as a result, with multiple companies suspending journeys through the Red Sea and taking a long diversion around Africa.
Vice Admiral Brad Cooper, who leads US naval forces in the Middle East, said the latest explosion happened in dense shipping lanes.
“It came within a couple of miles of ships operating in the area – merchant ships and US navy ships – and we all watched as it exploded,” he told reporters.
The attack happened a day after 12 countries – including the US and UK – warned the Houthis of “consequences” unless it stopped targeting commercial vessels.
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Vice Admiral Cooper has warned “there are no signs that their irresponsible behaviour is abating”.
US President Joe Biden has been under increasing pressure to respond militarily, something his administration has been reluctant to do in case it escalates tensions in the region further.
Although the Houthis have claimed their attacks specifically targeted vessels that had ties to Israel or were travelling there, many of the ships had no connection to Israel at all.
There are fears that the unrest could exacerbate the cost of living crisis here in the UK, affecting everything from energy bills to the price of consumer goods.
The route through the Red Sea is used by ships to access Egypt’s Suez Canal – a major shortcut linking the Mediterranean and Asia without the need to travel around Africa – to transport natural gas, electricals, and food and drink.
Ships are now being forced to travel south to the Cape of Good Hope and then north again around the Horn of Africa – adding 10 days and 3,500 nautical miles onto journeys.