French authorities say they opened a counterterror investigation after two women died in a knife attack at the main train station in the southern city of Marseille.
The assailant was shot dead by soldiers patrolling the area near Saint-Charles station, police said on October 1.
The extremist group Islamic State (IS) said one of its militants was responsible for the attack, according to the IS-linked Amaq news agency.
Police sources and witnesses were quoted as saying the attacker shouted “Allahu akbar” (God is greatest) as he carried out the attack.
The prosecutor's office in Paris said that a counterterrorism probe was opened.
"This act could be terrorist in nature but at this time we cannot confirm that," Interior Minister Gerard Collomb said.
President Emmanuel Macron said that he is "deeply outraged" by the "barbarous" attack.
France has been under a state of emergency since November 2015 attacks in Paris that left 130 people dead.
The government has deployed about 7,000 troops across the country to guard high-risk areas such as transport hubs, tourist sites, and religious buildings.