ISTANBUL

French prosecutors launched an investigation on Friday into a themed party in the country's northeastern Aube department in which participants dressed up as members of the Ku Klux Klan (KKK), a notorious US white supremacist group.

Troyes prosecutor's office opened the investigation "on the grounds of public provocation to hatred or violence on the grounds of origin, ethnicity, nation, race, or religion," according to broadcaster BFM TV.

"Witnesses have already been questioned, and technical investigations have been carried out. The investigation is ongoing, and the identified individuals—only two of whom reside in the Aube—will be questioned very soon," the prosecutor's office said.

According to a video posted on social media, five participants dressed up as members of the KKK, burned pallets, and pretended to strangle three other people who were wearing blackface in the event organized by the local club of the French Parachuting Federation (FFP) on Oct. 18.

Yves-Marie Guillaud, president of the FFP, immediately expressed outrage, calling it "a despicable and ignoble moral offense."

The three people wearing blackface were reportedly members of the Paris Fire Brigade, who announced on Wednesday that they had opened an internal investigation into the matter.