Justin Bieber has threatened to beat up a photographer.

The 19-year-old singer - who was hospitalised last night (07.03.13) after being taken ill during a concert in London - launched a tirade of abuse at waiting reporters as he was taken from his hotel to a waiting car earlier today (08.03.13).

After the 'Baby' singer got into the blacked-out vehicle, media were told to ''get back'' - before Justin reappeared from the car to confront a paparazzi he had heard making jibes about him.

He shouted: ''What did you say? What the f**k you say?''

The photographer - who had said as the star got into his car, ''f**k off back to America'', ''f**king little moron'' - responded, saying: ''You heard what I said ... you heard what I f**king said, mate.''

Justin replied: ''I'll f**king beat the f**k out of you.''

He took a swing at the photographer, but was kept back by his security guards before eventually being ushered back into the vehicle and driving away.

The 'Never Say Never' hitmaker later blamed his behaviour on a ''rough week''.

He tweeted: ''Ahhhhh! Rough morning. Trying to feel better for this show tonight but let the paps get the best of me.

''Sometimes when people r shoving cameras in your face all day and yelling the worst thing possible at u...well I'm human. Rough week

''Not gonna let them get the best of me again. Gonna get focused on this show tonight. Adrenaline is high now. Gonna put it on the stage

''Only way someone can break u is if u let them. (sic)''

Despite being taken ill with a shortness of breath, Justin - who caused controversy earlier this week when he arrived on stage for the first of his London shows two hours late - will go ahead with his final show in the city tonight.

A spokesperson said: ''Justin has been released from the hospital after a check-up and while he's feeling a little under the weather, he's planning on going ahead with tonight's show.''