Three people were stabbed at a railway station in Paris.
The attack, which took place at the main travel hub Gare de Leon, ended when police arrested a suspect.
One person was seriously injured after the accident, which occurred around 8am local time (7am in the UK).
The attacker, whose motives remain unknown, was armed with a sharp weapon.
French 24-hour news channel BFMTV reported that the attacker was 32 years old and from Mali.
He is said to have an Italian driving licence, according to the French newspaper Le Monde.
French Interior Minister Gerald Darmanin posted a message on social media in which he described the attack as an “intolerable act” and thanked those who arrested the attacker.
France's national railway company, SNCF, also posted on X to warn customers of disruption due to “an act of malicious intent”.
She said that the station's first and third halls were “temporarily inaccessible” due to the intervention of police and emergency services, with delays occurring between Paris Gare de Lyon and Montargis, and between Paris Gare de Lyon and Monteiro.
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Gare de Lyon is one of the busiest train stations in Paris. It is a hub for high-speed trains connecting the capital with other cities and for commuter trains serving the suburbs and towns in the Paris region.
Security measures have been strengthened in Paris ahead of hosting the Olympic Games at the end of July.
About 10,500 Olympians and millions of visitors will attend the event, with the opening ceremony scheduled for July 26.