Paris police attack: Four killed by knife-wielding employee

A knife-wielding employee has killed three officers and one administrative worker at police headquarters in the centre of the French capital, Paris.

The attacker, who has not been named, was shot dead by police.

Witnesses described scenes of panic, with many people fleeing the building in tears. The area in the île de la Cité has been sealed off.

The attack comes a day after police went on strike across France over increasing violence towards officers.

The Paris prosecutor said a murder investigation had been launched.

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A motive for the attack remains unclear. However, police union officials have suggested the attacker may have been involved in a workplace dispute.