French prosecutors said on Friday that the anti-terrorist police branch was deployed to investigate an attack which left one person dead and several wounded in southeast France.
A probe has been opened for murder and attempted murder in an organized group in relation to terrorism, the Paris prosecutor's office said in a statement.
French media said a decapitated head was found at the site, along with a flag bearing Islamist inscriptions.
A police source said he could not confirm the decapitation but said it seemed as though this was the case. One suspect had been arrested, a local official told BFM