Pete Doherty was arrested early on Monday on suspicion of drugs possession, a police source said. Doherty, 28, was arrested with two others, a man and a woman, after being stopped in a car in Tower Hamlets in east London.
The troubled singer, who has had an on-off relationship with supermodel Kate Moss, had been performing with his band Babyshambles at the V Festival in Staffordshire late on Sunday.
All three were taken to an east London police station where they remain in custody.
A Scotland Yard spokesman said: “At 2:30 a.m. officers in Tower Hamlets arrested a 28-year-old man on suspicion of possessing drugs.”
Doherty was warned by a magistrate earlier this month he faced a prison sentence if he failed to demonstrate he was trying to kick his drugs habit.
The singer pleaded guilty in July to possessing crack cocaine, heroin, cannabis and ketamine.