A woman rebel fighter (pic: Reuters)

British and US forces launched 112 cruise ­missiles on Colonel ­Gaddafi’s ­defences last night as the world finally lost patience with the Libyan tyrant.

They were fired from nuclear- powered submarines in the ­Mediterranean, demolishing 20 air defence sites around Tripoli.

Explosions were heard around 8pm UK time as the campaign began to blast the ­Libyan leader out of power.

David Cameron confirmed ­British forces had joined the ­offensive, after his emergency Cobra committee met at Downing Street.

The Prime Minister said: “We cannot stand aside and let this dictator murder his own people. Our thoughts are with our ­services, who are the bravest of the brave.” He added that the ­attacks were “necessary, legal and right”.

The first strike was launched by the French, whose jets dropped salvoes of bombs. The first was at 4.45pm – 6.45pm Libyan time – after Mr Cameron vowed “the time for action is now” at a dramatic meeting in Paris.

A French Defence Ministry spokesman said: “A first target was engaged and destroyed.”

Then 20 French jetscircling above Libya destroyed four tanks threatening rebel-held ­Benghazi city.

The attacks came the day after Gaddafi was warned he would feel the  “full force”  of Western powers if he ignored orders to stop terrorising his own people.

The attacks came at the end of a day that saw:

Gaddafi’s troops attacking ­Benghazi, with 26 rebel fighters reported killed.

A rebel jet blasted from the sky, plunging down in a ball of flame as the pilot ejected.

British, Canadian and ­Danish jets move to the Med as the Italians opened basesfor attacks.

Reconnaissance jets fly over Libya to spy on ­Gaddafi’s positions.