A fire broke out at the world`s biggest nuclear plant in northern Japan on Thursday but was extinguished and there was no leak of radioactivity, Tokyo Electric Power Co (9501.T) said, according to Reuters.

TEPCO, Asia`s top utility, is waiting for approval from three local governments to restart nuclear generators at the Kashiwazaki-Kariwa plant in Niigata, closed since it was damaged by an earthquake in July 2007.

A TEPCO spokesman said a worker who spotted the fire suffered a face injury and was taken to hospital.

The fire occurred inside a cooling pump at the plant`s No.1 nuclear unit.

The plant has seven nuclear generators and TEPCO is asking to be initially allowed to restart the No.7 generator, the newest and least damaged in the quake.