“Since the start of the year we've stopped seven plots which could have caused many deaths,” Collomb told CNews television channel.

He said a plot had been thwarted in the southern city of Marseille in April, a week before presidential elections, and could have had “dreadful” consequences, he said.

However a policeman was shot dead on the Champs-Elysées in Paris by an Isis sympathizer just days before the first round of the presidential election on April 23rd.

There have also been other attempted attacks on police and soldiers at Notre-Dame cathedral, the Louvre gallery, Orly airport and again on the Champs-Elysées since the start of 2017.

The extension of the state of emergency was approved on Thursday by the lower house of parliament.

It has been in place since November 2015 after a string of attacks in Paris left 130 dead, and has already been extended several times to cover events such as Euro2016 and the French elections.

New President Emmanuel Macron on Monday vowed to end the state of emergency “this autumn” by introducing a new security law which includes many of the emergency measures.

Twelve human rights groups including Amnesty International and Human Rights Watch called on lawmakers on Wednesday to drop the state of emergency and reject the new law.

Collomb said the law would enable the government to close down mosques where imams are deemed to be condoning terrorism. Closures could be ordered for six months at a time, on a rolling basis.

“Today there are three (mosques) that we want to close… since the start of the state of emergency we've closed 16,” he said.

French counter-terror police regularly stage simulations of terror attacks for training exercises in order to prepare for all eventualities.

Last month they staged an operation that simulated an attack on a TGV train (see pics below).