France charges three over neo-Nazi attack plot
The suspects, two men aged 29 and 56 and a 53-year-old woman, were indicted on Friday evening by a Paris anti-terrorist judge on suspicion of forming a "terrorist criminal association", the source added.
Three others also arrested on Tuesday -- two men and a woman -- have since been released.
Belonging to a group calling itself "Honour and Nation", the suspects are believed to have planned a violent attack, although they were not on the verge of carrying it out, a source familiar with the investigation said.
They were arrested based on their communications, research into explosives and scouting of the potential target.
The probe is just the latest into France's far-right scene.
Last month anti-terror prosecutors requested a trial for nine members of a group calling itself OAS that was dismantled in 2017, suspected of targeting senior politicians or French Muslims.
Another organisation suspected of planning attacks on Muslims, AFO, was taken down in 2018, the same year as still another group believed to have been preparing an attempt on President Emmanuel Macron's life.
Further anti-terrorist probes relate to a neo-Nazi group suspected of targeting Jewish and Muslim places of worship and to a white supremacist who admired the perpetrator of the 2019 attack on mosques in New Zealand city Christchurch.