A nuclear facility in Russia or Kazakhstan has led to the formation of a cloud of radioactive pollution over Europe.
According to revelations made by French nuclear safety institute IRSN, the leak had occurred in the last week of September. IRSN even speculated that the amount of Ruthenium 106 that had leaked was around 100-300 teraBecquerels.
"Measurement results from European stations communicated to the Institute since October 3 have confirmed the presence of Ruthenium-106 in the atmosphere of the majority of European countries," IRSN said.
If a similar accident was going to occur in France, there would have been a requirement to evacuate the accident site up to several kilometres.
An accident was ruled out by IRSN at a nuclear reactor, which was quoted by a dw.com report as saying that it had probably come from a nuclear fuel treatment site or a radioactive medicine centre.
No effect of the radioactive leak was observed in Europe's environment or on human health, IRSN confirmed. The exact place where the radioactive material released couldn't be spotted, the agency revealed.
According to the weather patterns, it appeared to have occurred in the zone south of the Ural mountains in Russia or Kazakhstan, an IRSN official said.
"Russian authorities have said they are not aware of an accident on their territory," IRSN director Jean-Marc Peres was quoted by Reuters as saying.
A Russian emergencies ministry's spokeswoman told the Guardian that she couldn't instantly comment.