One of the leaders of the "yellow vest" anti-government demonstrations, Eric Drouet, was detained by French police and placed in custody on Wednesday for organising a central Paris protest without declaring it, according to a source at the prosecutors office.
According to public broadcaster France Info, Drouet was with around 50 other Yellow vest protesters on their way to place candles at Place de la Concorde in honour of those people injured in the recent protests.
Other people were detained for identity checks.
AFP reported that Drouet had been on his way to meet other protesters gathered outside a McDonalds near the Arc de Triomphe, early Wednesday evening.
Drouet was arrested last month and faces a trial on June 5 for "carrying a prohibited category D weapon", a judicial source told AFP.
Radical leftist leader Jean-Luc Melenchon, a fierce critic of President Emmanuel Macron, tweeted: "Again Eric Drouet arrested, why? Abuse of power. A politicised police targeting and harassing the leaders of the yellow vest movement."
Man in custody for shouting "guillotine" at a visiting MP
In a separate incident, a 51 year-old man was in custody on January 2 for having shouted "guillotine" several times at an MP from President Macron's Republic on the Move party during a visit to the eastern Burgundy-Franche Comté region on December 20.
Authorities said he verbally assaulted Christophe Lejeune, an MP for the Haute-Saône department who had come to the Town Hall of Vésoul where he was picking up documents in connection with the Yellow Vest grievances.
Lejeune lodged a formal complaint to local authorities for threats to carry out a crime and threats against an elected official.
"This is a very rare type of complaint" said prosecutor Emmanuel Dupic.
"We are facing a challenge to the foundation of our democracy and we cannot accept these types of threats against an elected official" he cautioned.
The man, already known for involvement in other altercations during recent Yellow Vest protests, risks being sent to a criminal court where he could end up with a five year prison sentence and a fine of up to 75,000 euros.
After weeks of violence, and repeated clashes between protesters and police across France, Macron eventually scrapped the unpopular fuel tax rise and promised extra cash for minimum wage earners and tax cuts for pensioners.
But these measures have been given a lukewarm reception by many in the movement and a recent poll shows a considerable number of people believe the Yellow Vests' concerns will be largely ignored.
Although the number of protesters taking part in the demonstrations has dwindled since November 17, they have continued on a weekly basis.