The Sri Lankan Atomic Energy Authority (AEA) urged the public not to panic over the unfolding nuclear crisis in Japan.

According to AEA, the organization is in constant touch with the International Atomic Energy Agency (IAEA) in Vienna, Austria and the public will be kept informed.

A quake-stricken nuclear plant in Japan has been hit by a third explosion in four days, amid fears of a meltdown, BBC reported.

The blast occurred at reactor 2 at the Fukushima Daiichi plant, which engineers had been trying to stabilise after two other reactors exploded. The protective chamber around the radioactive core of reactor 2 has been damaged and radiation levels near the plant have risen, officials say.

Japanese Prime Minister Naoto Kan said the level of radiation at the plant had "considerably risen" and there was a high risk of radioactive material leaking out.

He added that the last remaining people within a 20km (12 mile) exclusion zone around the plant had to leave, and that those living between 20km and 30km from the site should remain indoors, BBC said.