Two women, aged 20 and 21, were brought to hospital following the incident in which they were apparently hit in the face with a corrosive substance.
One of the two women was suffering from partial loss of vision.
A 41-year-old female suspect has been arrested in connection with the attack.More news: Bitcoin Value Drops After Reports of Chinese Regulation
More on this as it develops.
The tourists - who are all in their 20s - were hospitalized, a spokeswoman for the prosecutor told the Associated Press. She spoke on condition of anonymity, per the French judicial system.
French authorities said they do not believe the attack is terrorism. Authorities are not releasing the identities of the victims and the suspect. The health of the other vitriolage victim is not yet known, and the two other victims, who were physically unharmed, are being treated for shock. The spokeswoman did not reveal the identities of the people involved or the circumstances behind the attack. After being arrested, she allegedly told the police: "I was a fool".
One attack, which was supposed to happen in April leading up to the French presidential election, was thwarted.