Nuclear blast 'over'

The French interior ministry has sought to allay fears after an explosion at a nuclear site killed one person on Monday, saying no one had been contaminated with radiation in the blast.

Investigations into the exact cause of the incident are ongoing, but it is believed that an oven used to melt radioactive metallic waste exploded and caught fire.

One worker was killed and four others were injured in the blast at the Centraco site north of Avignon.

French environment minister Nathalie Kosciuscko-Morizet visited the site late on Monday and met relatives of the victims.

Kosciuscko-Morizet said there was "no cause for concern," but added it was still not known why the blast had happened.

The government is being urged to ensure investigations are transparent and that the public is kept informed.

Greens party chief Cécile Duflo said the government had pledged to be transparent after the nuclear accident at Fukushima in March and that Monday's incident at Marcoule was an opportunity to prove it.

Environmental lobby group Greenpeace also demanded immediate transparency from the authorities.

No radiation leak

France's Nuclear Safety Authority (ASN) declared the incident "over" and under control within an hour of the explosion.

"This accident has no radiological risk or need for population protection," the organization said in a statement.

The Centraco site is a nuclear waste treatment center on the grounds of the Marcoule complex in the Rhone Valley, 30 kilometers (18.6 miles) north of Avignon.

Greenpeace campaigner Yannick Rousselet said it was "essential for the local population to be informed in real time about the situation and possible radioactive discharge."

He said the Centraco site had not been part of an audit of French nuclear sites, called after the Fukushima disaster. He added the site had been omitted from the most recent inspections carried out by the ASN.

The head of International Atomic Energy Agency, Yukiya Amano, said his organization had also requested "detailed information" about Monday’s blast.

Stuck to nuclear

Nuclear energy accounts for as much as 80 percent of electricity production in France.

It is estimated to be the world’s most nuclear-dependent country, and is a major exporter of nuclear power.

Following the Japanese reactor crisis at Fukushima, European Union leaders agreed to run "stress tests" on how their nuclear power plants would withstand earthquakes, flooding or terrorist attacks, and pledged to make the results public.

But France refused to shut down any of its reactors.

In June, French President Nicolas Sarkozy said France would stick to a plan to invest one billion euros ($1.36 billion) in future nuclear reactors.

Author: Zulfikar Abbany (AFP, AP, dpa)

Editor: Mark Hallam