A knife-wielding man has killed three police officers and an administrator in Paris this afternoon.
The incident happened at around 1pm French time at police headquarters nearby to Notre Dame Cathedral.
French media has claimed that the attacker was a 45-year-old man who had worked as an administrator for the force for two decades.
He was shot dead at the scene.
Union official Loic Travers said the incident appeared to have begun in an office and continued elsewhere inside the large police centre in the French capital.
He said the motive was unknown, but the employee allegedly responsible for the violence apparently never posed any problems before.
Mr Travers said he could not remember an attack on police officers of this magnitude.
Army soldiers patrol the area
The île de la cité area in the centre of the city has been sealed, and President Emmanuel Macron, Prime Minister Edouard Philippe and interior minister Christophe Castaner have all gone to the site.
Paris Mayor Anne Hidalgo has also attended, having confirmed on Twitter that “several people” had been killed.
She paid tribute to the victims on social media, saying “we know what we owe them”.
The Assemblée Nationale, France’s parliamentary centre, observed a minute’s silence in recognition of the attack.
The attack comes after police in Paris went on strike yesterday in a “march of anger” against issues including poor working conditions and rising hostility towards officers.