British Air Force Typhoon jets have operated alongside French aircraft in a coordinated attack on an underground arms cache in Syrian territory used by the Daesh militant organization, according to the UK's MoD.
The site, located using reconnaissance, was thought to be storing arms and explosives, the statement said, and was positioned in mountainous terrain just above the historic site of Palmyra in central Syria.
"The RAF jets utilized laser-guided Paveway IV weapons to hit a number of access tunnels down to the site... initial indications suggest the strike was effective," the MoD said.
There was no sign of any civilian casualties in the attack conducted Saturday night and each participating jet returned to base without incident, the MoD added.
The Typhoon FGR4s were backed up by a Voyager tanker plane.
Daesh - also known as Daesh - enforced extremist governance over parts of both Syria and Iraq until 2019.
"This action underscores our UK leadership, and resolve to operate in unison with allied nations, to eliminate any re-emergence of the terrorist group and their violent and radical beliefs in the area," UK Defence Secretary John Healey said.
RAF aircraft have performed surveillance missions over Syrian airspace to "forestall any efforts to regroup" of Islamic State subsequent to its military defeat at the climactic battle in Baghuz in 2019, the MoD reported.
"I must thank every member of our armed forces involved in this strike for their professionalism and their courage," Healey added. "They were among a great many British troops on duty over the holidays. This action, to take out dangerous terrorists who pose a risk to our security, highlights how our armed forces are prepared to act, throughout the year, ensuring Britain's security domestically and strong abroad."
In December, the US military executed what it described as a "major assault" against IS targets in Syria, subsequent to an attack killed two American soldiers and a local interpreter in the Palmyra area.
The United Nations estimates Daesh still has an estimated 5,000 to 7,000 militants in Iraq and Syria.
