PARIS (CNN) — Radical Muslims detained in France were preparing for holy war, a French prosecutor said Tuesday as the country widens a clamp down on suspected extremists in the wake of a deadly shooting spree last month.

The radical group Forsane Alizza and its founder Mohammed Achamlane were “calling for the establishment of an Islamic caliphate in France and calling for the implementation of Sharia law and inciting Muslims in France to unite for the preparation of a civil war,” Paris prosecutor Francois Molins said Tuesday.

He was speaking after police arrested 17 alleged radicals including Achamlane. Most of the suspects were due before a French anti-terror judge later on Tuesday.

The group was reportedly linked to Mohammed Merah, who was accused of killing seven people in the south of France in March before police killed him after a 32-hour siege of his apartment.

Molins said the investigation into Forsane Alizza began in October 2011, and the arrests were not connected to Merah’s rampage.

Achamlane “united around him a number of individuals who for several months had undergone physical training and received religious indoctrination in order to commit violent acts on French territory,” Molins told reporters Tuesday.

The radical leader was “known for his anti-Semitic stance and condemned for publicly violating French penal code,” the prosecutor said.

Members of his group held “discussions during a meeting held in Lyon in September 2011 about a plan to kidnap a judge based in Lyon,” he said.

But a lawyer for Achamlane rejected the accusations against his client, saying the arrests were related to France’s upcoming presidential election.

“These are statements that are not supported by any material facts. This affair is purely electioneering and politically motivated, that is all,” Philippe Missamou said on CNN affiliate BFM-TV.

Another of his lawyers, Benoit Poquet, released a statement denying any kidnapping plot.

The French Interior Ministry announced Monday it had deported two Muslims and plans to expel three more.

A statement by Interior Minister Claude Gueant said the moves were part of “an acceleration of the deportation procedures of foreign Islamic radicals.”

An Islamic militant from Algeria who was involved in 1994 attacks in Marrakech, Morocco, was sent to his home country Monday, the statement said. In addition, a Malian imam was returned to his home country for sermons that promoted anti-Semitism and rejection of the West, it said.

Deportation proceedings also have started or are planned against three others: an imam of Saudi nationality, a militant Islamist from Tunisia and an imam from Turkey, the statement said.

It cited provisions in the law governing aliens and political asylum, saying the statutes “allow this type of decision with regards to the ‘urgent need for state security or public safety’ or ‘conduct likely to harm the fundamental interests of the state.'”

According to the statement, other expulsions will occur soon.

The raids came a week after gunman Mohammed Merah, who killed seven people, was shot dead after a long siege in the southwestern city of Toulouse.

French President Nicolas Sarkozy, who is running for re-election, said the raids were intended to “deny the entry of certain people to France” who did not share the country’s values.

“It’s not just linked to Toulouse. It’s all over the country. It’s in connection with a form of radical Islam, and it’s in agreement with the law,” he said.

Sarkozy suggested then that more raids would follow, saying, “There will be other operations that will continue and that will allow us to expel from our national territory a certain number of people who have no reason to be here.”

Merah was blamed for the killings of three French paratroopers, a rabbi and three Jewish children ages 4, 5 and 7. Two other people were seriously wounded in the shootings.

— CNN’s Rachel Ramsay, Tom Cohen and Alex Felton contributed to this report.