Rock star Pete Doherty is in custody again after his arrest on suspicion of administering noxious substances.
Pete Doherty is currently on bail after being arrested last week
He was arrested in east London after a newspaper published pictures allegedly showing him taking drugs and injecting into the arm of a female fan.
He is due to be questioned at Stoke Newington police station where he remains in custody.
His arrest came hours before he was due to play at an anti-racism concert with band Babyshambles in Trafalgar Square.
Doherty is already on police bail after being arrested on suspicion of possessing class A drugs last week.
Babyshambles drummer Adam Ficek told the BBC that police had "busted into" the singer's London flat and arrested him.
Police confirmed Doherty had been arrested on a street in east London at 0800 BST on Saturday.
He is currently being held under Section 23 of the Offences Against the Person act.
The free Love Music Hate Racism event - which aimed to unite people in the fight against fascism and Islamophobia - featured performances by Belle & Sebastian and a speech by the director of Bend It Like Beckham, Gurinder Chadha.
Organisers said the event also featured dance, poetry and music by children from youth groups.
Derek Simpson, Amicus General Secretary, who spoke at the rally, said: "Events like these that bring people together are vital to helping suppress the threat we face from racist organisations."
Scotland Yard said an estimated 3,000 people attended the concert and rally.