Russia says there has been a radiation leak at a nuclear reprocessing plant in the Ural mountains east of Moscow, but that it has not harmed anyone.
Local emergency officials say a faulty tap allowed radioactive waste to leak from a tank onto a stretch of road at the Mayak plant last Thursday.
Radiation levels inside and outside the plant are normal, the officials say.
The plant was a top secret Soviet atomic weapons facility. In 1957 it was the scene of a major nuclear accident.
In the latest incident, a violation of safety rules was blamed for the leak.
Russian prosecutors are considering whether to open a criminal case.