Two British tourists are said to have been injured by a knifeman who went on the rampage in the centre of Paris before locals playing petanque tried to stop him with boules.
French police have arrested the knife-wielding attacker who injured seven people in the capital, four of them seriously.
The man, who was reportedly carrying a knife and an iron bar, is said to have stabbed three people outside a cinema, the Daily Mail reports.
The attacker, who was described as an Afghan national, went on to target other victims in the head and chest, Le Parisien reports.
One of the Brits was particularly badly hurt by "a stab in the head", while the other was "cut in the chest".
The attack reportedly unfolded around 10.45pm local time.
A witness playing petanque is said to have made an attempt to foil the attack by throwing a boule at the assailant.
Four of the people are said to be seriously injured, while the suspect is an Afghan national.
The victims were all rushed to local hospitals, where their conditions were described as "serious but not life threatening". The attacker is not thought to have been badly injured by officers.
There was no initial sign that the attack was linked to terrorism, a judicial source said.
"Nothing at this stage shows signs of a terrorist nature in these assaults," the source close to the inquiry said.
The case is being investigated by judicial police, with Paris prosecutors opening an official inquiry.