Police in Paris say seven people have been injured by an attacker armed with a knife and a metal bar.
The incident happened in the Quai de la Loire just before 11pm local time on Sunday night, on the banks of a canal.
According to local media reports, two British tourists were among those injured.
The UK's Foreign Office told BBC it was 'urgently investigating' the incident following the reports of injured Britons.
Four of the victims are said to be in a 'severe condition' after being attacked, while all seven have been taken to hospital for treatment.
One man, reported to be an Afghan national, has been arrested following the knife attack.
However, Reuters reports there was 'no initial indication' that there was a terrorist motive behind the attack.
Quai de la Loire is located in the north-east of the French capital, with broadcaster BMTV reporting the stabbing took place near a cinema in the area.
