Madrid - Radioactivity has been found on a lorry which transported scrap metal from a Spanish nuclear plant where a leak occurred in November, the Nuclear Safety Council (CSN) said Tuesday.

The discovery could mean that radioactive particles have been carried to a distance of dozens of kilometres outside the Asco I plant, instead of remaining within its confines, as had been believed so far, according to media reports.

The lorry took scrap metal from the Asco I plant near the eastern coastal city of Tarragona to a nearby dumping site. The metal itself was not contaminated, the CSN said.

The discovery meant that 1,600 people would have to undergo health checks, twice as many as had been planned, the daily El Mundo said on its website.

The director and protection chief of the Asco I plant were sacked recently after the leak (which occurred during refuelling) turned out to have been 100 times more serious than the plant said in its initial report to the CSN.

Radioactive particles have been discovered within the plant complex until recently.

More than 500 people have already undergone health checks, including employees of the nuclear plant and others, including visiting schoolchildren, who entered it. No evidence of health damage has been found so far.

The Asco I plant faces a fine of up to 20 million euros (32 million dollars). The environmental group Greenpeace has sued the plant, and asked the European atomic energy agency Euratom to intervene. (dpa)