A knife-wielding man who worked at police headquarters in central Paris went on a rampage Thursday, stabbing to death four employees before himself being shot dead, officials said. A fifth person was critically injured and was being treated in hospital after the deadliest attack on police in France in years, the motive of which was still unclear.

Sources close to the investigation said the attacker, a 45-year-old IT worker in the police intelligence department, had converted to Islam 18 months ago. He killed three male officers and a female assistant before being shot in the courtyard of the square stone building next to Notre-Dame cathedral in the historic heart of Paris.

The man, who was born in the French Caribbean territory of Martinique and had worked for the police since 2003, had a hearing disability. Police searched his home in a quiet residence in Gonesse, a low-income suburb north of Paris, and took his wife into custody, Paris prosecutor Remy Heitz told reporters.

Interior Minister Christophe Castaner said the assailant had "never shown any behavioural problems". The police were "particularly stricken by this exceptionally grave incident", said Castaner, who postponed a planned trip to Greece and Turkey to visit the scene with President Emmanuel Macron.

Copyright Agence France-Presse, 2019