PARIS: Ten people, including police officers and the head of a company that distributes Tasers, have been detained in an investigation of alleged spying on a far-left politician who had denounced the use of stun guns, a police official said.

Olivier Besancenot, leader of the Communist Revolutionary League and a candidate in the presidential election last year, denounced what he called an “operation of spies, of crooked cops” and said that there was “cooperation between private eyes and police.”

France-Info radio and BFM TV reported that 4 of the 10 detainees were eventually freed but not the head of the Taser distributor, Antoine Di Zazzo, whose company has filed a suit against Besancenot.

Others detained included a customs official and the head of a private detective agency, according to a police official who requested anonymity. He asked not to be identified because he was not authorized to publicly discuss the investigation.

The detentions were the result of a legal complaint filed by Besancenot in May after the news weekly L’Express reported that his wife had been followed and their bank accounts had been consulted from October 2007 until January 2008.

The prosecutor’s office then opened an investigation, which led to the detentions Tuesday.

Besancenot has called for a moratorium on Tasers and claimed at a news conference that investigators “appeared to have made a link” between his criticism of the stun guns and the alleged spying. His statement could not immediately be confirmed.

Di Zazzo heads SMP Technologies, which distributes Tasers in France, including to the police. The firm had filed suit against Besancenot for “defamation” after he alleged the stun guns were responsible for 150 deaths in the United States.

Besancenot received 4.08 percent of the vote in the first round of presidential elections in April 2007 - nearly 1.5 million voters.

He is preparing to start a new party that would bring together far left groups in France.