French prosecutors have launched a terror probe into the fatal stabbing of a French police officer inside her police station near the historic Rambouillet chateau outside Paris.

Fellow officers shot and killed the suspected attacker at the scene.

The identity and motive of the assailant were not immediately clear, a national police spokesperson told the Associated Press.

The police officer was a 49-year-old administrative employee in the station, the spokesperson said.

The national anti-terrorism prosecutor’s office said it had taken over the case and opened an investigation into murder of a person of public authority in relation with a terrorist group.

“We are in a state of astoundment,” Karl Olive, vice president of the regional council, said on BFM television.

The attack took place south-west of Paris just inside the police station in a quiet residential area of the town of Rambouillet, about 750 metres from a former royal estate that is sometimes used for international peace negotiations.

Police cordons ringed the area after the stabbing.

French Prime Minister Jean Castex, interior minister Gerald Darmanin and other top officials visited the scene of the attack to show their support for police.

“Police are symbols of the republic. They are France ” Valerie Pecresse, president of the Paris region, told reporters at the scene, adding that “the face of France” was targeted.

France has seen deadly attacks against police in the past, including some by Islamic extremists.

The attack comes as President Emmanuel Macron’s government is toughening its security policies, amid voter concerns about crime and complaints from police that they are in increasing danger.

Mr Macron may face a challenge from French far-right leader Marine Le Pen if he seeks a second term in France’s presidential election next year.