RAF use Brimstone missiles for first time in Syria

The attacks targeted an IS vehicle and tunnels near the town of Raqqa, as well as the Omar oilfield in the east of the country near the border with Iraq, said Downing Street.

Brimstone is a "fire-and-forget" radar-guided precision weapon which can be used against moving targets, which was cited by Prime Minister David Cameron in the run-up to last month's vote on war in Syria as the kind of UK asset which would make a "meaningful difference" to the coalition's battle against IS.

The four missions taking place over the course of Sunday involved:

- Two Tornado GR4 jets using a Brimstone missile to destroy a supply truck near Raqqa and targeting two IS buildings in the area, including a command and control centre, with Paveway IV laser-guided bombs;

- Reaper unmanned drones targeting an IS terrorist position in the Raqqa area with a Hellfire missile;

- Two Tornado jets striking a tunnel complex near Raqqa with four Paveway bombs.

- An attack on the Omar oilfield by two Tornados and a Reaper drone, which used used three Brimstones as well as Hellfire missiles to attack a number of mobile cranes brought in by IS to attempt to repair damage inflicted by previous RAF and coalition air strikes.

On Monday morning, an RAF Reaper flew the 1,000th drone sortie against Islamic State - also known as Daesh, Isis or Isil - since the beginning of operations in October 2014, said the Ministry of Defence.

Asked whether Sunday's missions indicated the UK was stepping up the tempo of its fight against IS in Syria, Mr Cameron's official spokeswoman said: "This is part of the ongoing operation and work we are doing with coalition partners to defeat Daesh in Iraq and Syria.

"We have always been clear that it is going to take time and require patience and persistence, but it reflects the fact that where we identify targets and an ability to strike them, we will do all we can to tackle Daesh."

No details were made available of casualties resulting from the raids.

But the PM's spokeswoman stressed that the UK military is operating under instructions to avoid civilian deaths: "As you know, we have very clear guidelines in place for the military about their targeting and striking. This was focused on Daesh terrorists and their resources."

The spokeswoman said that the choice of the Brimstone missile to target militants was an operational one.