Iran has targeted the US Navy base in Bahrain, highlighting gaps in air defences, which will worry Washington and its allies in the region.
Videos appear to show missiles and drones striking the vicinity of the US Fifth Fleet headquarters in Bahrain.
As yet there are no reports of casualties. The US military will likely have had some warning of the attack and taken precautions to evacuate personnel.
Tom Sharpe, a former Royal Navy Commander, says Bahrain was likely seen by Iran as a high profile target that has, in the past, had relatively little in the way of air defences.
That now appears to have been highlighted by video showing a relatively slow-moving Iranian Shahed drone breaching its defences. In Ukraine such drones can often be shot down with a simple high calibre machine-gun.
