Keira Knightley felt "threatened" by a man arrested on suspicion of stalking her.

The British actress - who is currently starring in the West End show 'The Misanthrope' at London's Comedy Theatre - called police last Thursday (04.02.10) after she was constantly bothered by 41-year-old Mariek Daniluk, who would regularly turn up at the theatre to see her.

A source told The Sun newspaper: "Keira felt threatened by this guy who turned up a number of time and tried to speak to her. He did not make any specific threats to her but she was concerned enough to call the police."

Police have confirmed the man was arrested outside the theatre over harassment allegations.

A spokeswoman for the Metropolitan Police said: "A 41-year-old man was arrested on suspicion of harassment on Thursday (04.02.10). The arrest follows concern expressed by a woman."

Polish national Daniluk - who lives in Palmers Green, North London - was held in prison overnight and questioned by officers yesterday (05.02.10).

He was charged with harassment and is due to appear in the City of Westminster Magistrates Court today (06.02.10).

This is not the first time Keira has been panicked by stalkers.

Two years ago, the 24-year-old beauty moved to America after developing five stalkers.

At the time she said: "I'm frightened out of my wits every time I see one of them."