Within an hour of the historic vote in parliament last night, planes were in the air
RAF Tornado jets have carried out the first British air strikes on Islamic State (IS) in Syria.
The UK's Ministry of Defence says their bombs hit six targets at oil fields in the eastern part of the country.
Planes took off from a British air base in Cyprus just one hour after MPs last night voted overwhelmingly to back the bombing campaign.
In a statement today, the Ministry of Defence said:
"The mainstay of Daesh’s financial income is derived from exploitation of a number of oilfields that they hold. These are overwhelmingly located in Daesh’s heartlands in eastern Syria. Several of these oilfields have already been effectively targeted by other coalition partners; RAF aircraft and precision weaponry are well suited to attacking, with low collateral risk, this type of target."
The UK estimates the oil fields they hit represent over 10% of IS potential income from oil.
Authorities insist they took precautions to ensure civilians were not hit: "Before our aircrew conducted their attacks, as is normal they used the aircraft’s advanced sensors to confirm that no civilians were in the proximity of the targets, who might be placed at risk."
RAF raids will continue in eastern and northern Syria over coming weeks.
Foreign Secretary Philip Hammond has said the Government will not give a running commentary on operations in Iraq and Syria, but the Ministry for Defence has been updating the public via its Twitter account.
They have also given information about more planned strikes later:
Last night anti-war protesters staged a demonstration outside Parliament in London:
British Prime Minister David Cameron says MPs have taken the "right decision to keep the UK safe".
They voted by 397 to 223 in favour of the action on Wednesday night - giving the government a majority of 174.
US President Barack Obama welcomed the UK's vote - saying it demonstrated the coalition's "unity and resolve".
France - which began bombing IS targets in Syria in September - said it showed Europeans will stand together after the terror attacks that left 130 dead in Paris last month.