New Incident at French Nuclear Plant
ASN said two fuel units became snagged in a reactor at Tricastin in southern France on Monday morning when site workers were attempting to remove them during maintenance work.
The work was interrupted and the reactor building evacuated, it said, but site workers were not affected and there was no external leak. The incident was still being dealt with on Monday evening.
EDF, which operates the site, has proposed classifying the incident at 1 on the International Nuclear Event Scale, which ranges from zero to 7. ASN said it had not yet taken a decision.
The incident is the latest of several that have highlighted safety concerns in France's nuclear industry, the biggest in Europe, accounting for 80 percent of French power generation.
In July, 30 cubic metres of liquid containing non-enriched uranium was accidentally poured onto the ground and into a river at Tricastin, prompting safety checks at all of France's 19 nuclear sites.
Weeks later, around 100 staff at the site were contaminated with a low dose of radiation.
(Writing by James Mackenzie; Editing by Catherine Evans)