A French minister has warned that violent demonstrators intend “to destroy, to injure and to kill” as trade unions held more marches and strikes on Tuesday against controversial pension reforms.

Fears that violence could mar demonstrations planned across the country prompted what interior minister Gerald Darmanin described as an unprecedented deployment of 13,000 officers, with nearly half of them concentrated in Paris.

He said that more than 1,000 “radical” troublemakers, some from overseas, could latch on to planned peaceful marches in Paris and other cities.

France Seething Streets
French president Emmanuel Macron is under fire over pension reforms (Thomas Padilla/AP)

“They come to destroy, to injure and to kill police officers and gendarmes. Their goals have nothing to do with the pension reform. Their goals are to destabilise our republican institutions and bring blood and fire down on France,” the minister said on Monday in detailing the policing measures.

Union leaders and political foes of President Emmanuel Macron blame his government for protest violence that has flared in recent weeks, saying his pension reforms are sparking it.

Critics also allege that police officers are using excessive force against protesters. A police oversight body is investigating multiple claims of wrongdoing by officers.

The new wave of strikes and protests was the 10th time since January that unions have called on workers to walk out and for demonstrators to flood the streets in protest against Mr Macron’s push to move back France’s legal retirement age from 62 to 64.

Unable to get a majority in parliament’s lower house for the unpopular reforms, Mr Macron rammed them through using a special constitutional power, further inflaming protesters’ anger.