Prosecutors later said they had ended their questioning of the suspect, a Malian national, due to his “incompatible” mental state and placed him in police custody for psychiatric care.

The man went on a stabbing spree at 7:35 am (06:35 GMT) at the station, which operates domestic trains as well as those heading to Switzerland and Italy.

One person suffered life-threatening injuries to the abdomen while two others were lightly wounded, Paris police prefect Laurent Nunez told reporters. A fourth person went into shock after witnessing the assaults.

The stabbing took place less than six months before Paris hosts the 2024 Olympics and an expected 15 million visitors.

Paris prosecutors said the suspect might have used a knife and a hammer that were under analysis.

“The suspect did not cry out (any religious slogans) during his attack,” a police source said. “He presented the police an Italian driving licence”, which gave his date of birth as January 1, 1992.

His Italian papers were in order, showing he had lived legally in the country since 2016 and had no criminal record. The suspect volunteered to police that he suffered from “psychiatric problems” and he was carrying medicine, said Nunez.

“We will see if terrorism can be ruled out, after checks underway on his telephone records, life in Italy and comments to investigators,” Nunez added.

Passers-by overpowered the man before railway police arrived on the scene, the police source said.

“A thank you to those who overpowered the man who carried out this unbearable act,” said Interior Minister Gerald Darmanin on X, formerly Twitter.

Ce matin à la Gare de Lyon, un individu a blessé 3 personnes à l’arme blanche avant d’être interpellé. Une personne est blessée gravement. Deux autres le sont plus légèrement. Elles ont été prises en charge par les services de secours. Merci à ceux qui ont maîtrisé l’auteur de…

— Gérald DARMANIN (@GDarmanin) February 3, 2024

The attackers’ motives remained unclear.

The Paris prosecutor’s office launched an inquiry into the attack, while the national anti-terrorist prosecutor said it was observing proceedings at this stage.

The assault took place less than six months before Paris hosts the 2024 Olympics and and an expected 15 million visitors.

Each year more than 100 million passengers go through the Gare de Lyon, France’s biggest mainline hub.

The area between halls one and three were temporarily inaccessible, rail operator SNCF said on X, formerly Twitter. Services to the Paris region were delayed, the SNCF said, referring only to “an act of criminal intent.”