The chaotic life of Amy Winehouse took another twist last night after the troubled star was arrested on suspicion of assault outside a Camden bar.

On the same day that her husband, Blake Fielder-Civil, appeared in court charged with attempting to pervert the course of justice and inflicting grievous bodily harm, Ms Winehouse attended Holborn police station voluntarily yesterday afternoon to answer questions about Wednesday’s alleged attack. She was then arrested and was still in custody last night.

It is understood that she was accused of attacking two men, head- butting one and punching another, in the early hours of Wednesday.

A spokesman for Scotland Yard said that a doctor had examined Ms Winehouse and that she was deemed “unfit to be interviewed”. As a result, it was expected to take at least four hours before she could be dealt with. The arrest came less than a week after the Grammy award-winning singer made her debut in the Sunday Times Rich List.

The singer arrived at Holborn police station at about 5.10pm, nearly three hours after she had been expected. Hundreds of fans had gathered during the day. When she arrived finally, amid the crowds of assembled fans and photographers, she was visibly aggravated and upset.

The singer, who had a mystery blotch on her right cheek, pulled up by the station in a silver Mercedes van with blacked-out windows. Her two bodyguards, who had been at the station for four hours themselves, then took positions flanking the door while another of her minders stood by.

There was a delay before the car door opened. Ms Winehouse then dived out of the van and dismissed the protective arm of one of her minders. Scowling at photographers and fans she strutted a couple of steps before breaking into a run up the stairs and into the police station. She was wearing a sleeveless yellow T-shirt, khaki denim shorts and a black belt.

Ten minutes before her arrival her legal team entered the police station. A Scotland Yard spokesman said last night: “A 24-year-old woman has been arrested on suspicion of assault after attending a Central London police station by appointment. She is currently being held in custody.”

Reports said that Ms Winehouse was accused of attacking two men in the early hours of Wednesday, head-butting a man who tried to help by hailing her a taxi and punching a second man in the face. Ms Winehouse, whose troubled personal life has eclipsed her musical success, she has sought help repeatedly for drug addiction. Mr Fielder-Civil is in jail awaiting trial on charges of conspiracy to pervert the course of justice.

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