French officials say that two women have been killed in the attack by a man with a knife at Marseille's main train station, including one whose throat was slit.
The officials say soldiers then fatally shot the attacker. Police have evacuated the Saint Charles station, with officers and soldiers taking up positions outside.
The officials spoke on condition of anonymity because they weren't authorized to discuss an ongoing investigation.
The Paris prosecutors' office says that a counter-terrorism probe has been opened, but no motive for the attack has been immediately given.
French police have warned people to avoid Marseille's main train station amid reports of a knife attack.
Marseille police said an operation "is underway" on its official Twitter account. No other details were immediately available.
French television BFM TV says at least one person has been stabbed, and the assailant has been shot dead.
Interior Minister Gerard Collomb tweeted that he's going immediately to the scene "after the attack perpetrated near Saint Charles train station."
The train station has been evacuated.
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