In a statement released after a morning meeting, the watchdog said the leaked data had been "fraudulently" obtained and that fake news has probably been mingled with it.
The front-runner in the French presidential election, Emmanuel Macron, has said that the European Union, EU, must reform or face the prospect of "Frexit".
Projected results in the ongoing French presidential election have it that two of the major contenders, Emmanuel Macron and Marine Le Pen are through to the runoff election coming up in May.
The Eta militant group killed more than 800 people in some 40 years of violence as it sought to carve out an independent country straddling Spain and France.
