Robert Downey Jr dropped from Ally McBeal after arrest

Robert Downey Jr has been sacked from Ally McBeal, hours after being arrested for investigation of being under the influence of drugs.

The arrest is the latest in a string of substance-abuse troubles for the actor.

Downey was walking in Culver City, near Los Angeles, at the time of the arrest.

Police have not released details about what led to the arrest, or of what type of drug he is accused of using.

Downey, 36, of Malibu, was held for several hours, issued a citation and released to his parole agent, who arranged for him to enter a detoxification centre.

The actor must appear in court on May 4.

Ally McBeal's producer David E Kelley released a statement saying that he had scuttled plans to feature Downey in several more episodes.

The producer had publicly supported Downey until his latest arrest, even signing him to more episodes after the actor's arrest last November on drug charges.

Downey's role as Ally McBeal star Calista Flockhart's boyfriend won him a Golden Globe Award and is credited with boosting ratings for the comedy.

In a separate incident, Downey is due in court on Monday over alleged drug possession last November.