Police in China have detained four people after radioactive material being used in a construction project went missing, state media reported on Monday.
A tiny piece of irridium-192, used to locate flaws in pieces of metal, vanished on Wednesday from a construction site in the eastern city of Nanjing and was not recovered until Saturday afternoon, the official China Daily reported.
It was found in bushes 1km from the construction site wrapped in a plastic bag, put in a lead container and then taken away, the newspaper said.
Police have detained four people deemed responsible for its loss from an engineering company, the paper added.
Nobody is reported to have become sick because of the incident, it said.
However, the newspaper added that Nanjing authorities only announced the material had gone missing on Saturday, even though information about the incident began leaking onto the internet the previous night.
The Global Times, an influential tabloid published by the ruling Communist Party’s official People’s Daily, said the delay in releasing information had been to prevent mass panic, though added this could be considered dereliction of duty.
China has become increasingly sensitive to environmental issues, due to anxiety over worsening pollution among its increasingly well-educated and affluent population.