An Afghan national who left seven people, including two British tourists, badly injured after he attacked them with a knife and an iron bar in a popular Paris area has been charged with attempted murder and detained, a judicial source said Wednesday.

The suspect, aged 30, has been held since the attack late Sunday caused panic and mayhem in the busy Stalingrad area of northeastern Paris. He was presented before a judge Wednesday and formally charged, the source said.

The motivation for the attack was still not known and the investigation has not so far found evidence to classify it as an act of terrorism, another source close to the inquiry said.

The source said investigators were still trying to establish the man's identity but have ascertained that he arrived in France in June.

The suspect was overpowered by bystanders who tried to stop him by throwing heavy metal petanque balls at him.

Unconscious when officers arrived on the scene, he was taken to hospital.

Police said at the time that there was nothing to suggest it was a terrorist attack.

Among the seven injured in the attack were two British tourists and an Egyptian visitor.

France has been on high alert following a series of deadly jihadist attacks in recent years, often by people who have become radicalised or claim to have acted in the name of the Islamic State.

More than 240 people have been killed by Islamist extremists since a massacre at the Charlie Hebdo satirical magazine in Paris in January 2015.