The International Atomic Energy Agency (IAEA) on Friday confirmed that four nuclear plants in Japan close to the epicenter of a massive earthquake have been safely shut down.

A statement from IAEA said it was seeking more information on which countries and nuclear facilities might be affected.

The 8.8 magnitude earthquake hit Japan's northeastern Honshu Island Friday, triggering tsunami warning issued to at least 20 countries and regions.

According to earlier reports, Japanese Prime Minister Naoto Kan had said there were no reported leaks of radioactive materials from power plants.