Updated

A French prosecutor wants to drop a decade-long investigation into the fallout in France from the 1986 Chernobyl nuclear accident, citing lack of proof that it caused health problems.

The prosecutor argued in a Paris hearing Thursday that the probe has been inconclusive and should be abandoned, according to a judicial official. The official was not authorized to be named because the hearing was closed to the public.

The hearing came amid global worries about the risks of fallout from Japan's nuclear disaster, as Japanese authorities struggle to contain radiation from reactors destroyed by the earthquake and tsunami earlier this month.

Investigators said that the head of the French radiation safety agency at the time of the Chernobyl accident deliberately misled the public by minimizing the health risks in France from the radioactive cloud it produced.

The safety agency chief, Pierre Pellerin, is the only person who has been handed preliminary charges in the case. He has insisted on his innocence, and the prosecutor said there was no evidence he misled the public on purpose.

Researchers and cancer victims accuse the government of downplaying the effects of the Chernobyl explosion, partly to protect France's powerful nuclear industry. A few dozen people, including thyroid disease victims, staged a protest Thursday near the courthouse.

French authorities have been widely ridiculed for insisting after the Chernobyl accident that the radiation did not reach France, though neighboring countries all said it passed through their skies. Other European countries pulled milk from shelves or recommended that children take iodine tablets to reduce radiation risks, while France took none of these steps.

French government agencies have adjusted some of their initial radiation estimates since the accident, but deny any intentional deception.

The Paris appeals court will decide Sept. 7 whether to abandon the investigation. Until that decision is made, the probe is effectively frozen.

Since the Japanese nuclear troubles began, French nuclear safety authorities have taken pains to soothe the French public about potential risks, holding daily press conferences for two weeks after the tsunami.

The court hearing comes amid renewed questions about the safety of nuclear plants, and second thoughts by many countries about re-investing in nuclear energy. France is the world's most nuclear energy-dependent country, with more than 70 percent of its electricity coming from nuclear reactors and has been at the forefront of a recent so-called nuclear renaissance.