Western aircraft have been conducting patrols to stop a resurgence of the Daesh militant group that ruled parts of Syria until 2019.

Intelligence analysis identified an underground facility believed to be used to store weapons and explosives in mountains north of Palmyra, Britain said.

“Our aircraft used Paveway IV guided bombs to target a number of access tunnels down to the facility; whilst detailed assessment is now underway, initial indications are that the target was engaged successfully,” Britain’s defence ministry said in a statement.

Britain said the area was “devoid of any civilian habitation” before the attack and that all its aircraft had returned safely.

“This action shows our UK leadership and determination to stand shoulder to shoulder with our allies, to stamp out any resurgence of Daesh and their dangerous and violent ideologies in the Middle East,” British Defence Secretary John Healey said.

Britain said it used Typhoon FGR4 combat jets to bomb the target, supported by a Voyager refuelling tanker.