Some 2,500 people took part in a large-scale evacuation drill Thursday to mark the fifth anniversary of Japan's worst nuclear radiation accident, which occurred at an atomic fuel reprocessing plant in Tokai, Ibaraki Prefecture.

In addition to the extensive evacuation and scanning for radiation exposure of residents, the drill included for the first time the transport by helicopter of plant employees exposed to radiation to the National Institute of Radiological Sciences in Chiba Prefecture, about 100 km away.

The drill was aimed at raising awareness on disaster preparedness and crisis management in the event of a nuclear disaster.

It involved about 500 residents and 2,000 staff members of the prefectural and municipal governments, as well as other organizations. The drill began at 8:30 a.m. under the scenario of a nuclear accident with external radioactive leakage having taken place at a reprocessing plant of the Japan Nuclear Cycle Development Institute in Tokai.