"Extremely radicalized" girl posted Daesh appeals in a Telegram chat propagating radical Islamism and expressed her resolve to commit a terrorist attack, a source familiar with the case was cited by BFMTV broadcaster as saying.
The prosecutor's office in Paris opened judicial inquiry into the case, the news outlet added.
France has recently fallen victim of two terror attacks, the responsibility for which has been claimed by Daesh, outlawed in many countries worldwide including Russia. On July 14, a truck rammed into a large crowd celebrating Bastille Day in Nice, killing at least 85 people.
On July 26, two armed men took five people hostage at a church in Saint-Etienne-du-Rouvray, killing the priest before themselves being taken out by French security forces.
