A heavily armed man opened fire on a high-speed train travelling from Amsterdam to Paris on Friday, injuring two people before being overpowered by two American passengers.

The motives behind the attack were not immediately known, although French prosecutors said a probe was being launched by counter-terrorism investigators.

France has been on edge since Islamist gunmen went on the rampage in January, killing 17 people in the capital Paris.

The assailant was arrested after the train pulled into the station in the northern French town of Arras, a spokesman for the French state rail company SNCF told AFP.

According to the initial French investigations, the gunman was known to French intelligence services and was Moroccan or of Moroccan origin and aged 26.

The man was carrying several weapons in his luggage, including guns and razor blades, one source close to the case told AFP, with some reports that he was armed with a Kalashnikov.

"The anti-terrorist section of the prosecutor's office has taken this case, in agreement with the local prosecutor, in view of the weaponry used, the way it happened and the context," the prosecutor's office said.

- 'Everything being done' -

French President Francois Hollande said in a statement that "everything is being done to shed light" on the shooting.

Prosecutors said the gunman was overpowered by two American passengers.

An American and a Briton were reportedly among those hurt in the attack.

The French actor Jean-Hugues Anglade, who appeared in the 1986 cult film "Betty Blue" staring Beatrice Dalle, was lightly injured in the incident, a witness told AFP on condition of anonymity. He had reportedly been hurt breaking the glass to activate the train's alarm.

French Interior Minister Bernard Cazeneuve went to Arras in the wake of the incident, which occurred shortly after 6.00 pm (1600 GMT), his ministry said.

His spokesman Pierre-Henry Brandet confirmed to AFP that a man had opened fire on the train.

"We do not know the identity of this individual nor his motives," said Brandet, adding: "It is too early to speak of a terrorist link."

The SNCF spokesman had said earlier that three people were injured, two of them seriously, and that at least one suffered gunshot wounds.

"The passengers are safe, the situation has been brought under control," train operator Thalys said on Twitter.

Thalys said on its website that several trains had been delayed after the "intervention of security forces at Arras station".

"The train is at the station and emergency services are at the scene," said Thalys, which is jointly owned by the national rail companies of Belgium, France and Germany.

France remains on edge after Islamic extremists attacked the satirical magazine Charlie Hebdo and a Jewish supermarket in Paris in January, killing 17 people.

In June, a man beheaded his boss and tried to blow up a gas plant in southern France in what prosecutors say was an attack inspired by the Islamic State group.
Source: AFP