TOKYO - The Japanese government on Tuesday decided to establish an independent expert panel to probe into the causes of the ongoing nuclear crisis at the Fukushima No.1 nuclear power plant.

Yotaro Hatamura, an emeritus professor at the University of Tokyo would lead the panel, Deputy Chief Cabinet Secretary Yoshito Sengoku said at a news conference.

Sengoku said the panel would be eligible to access related documents and question people concerned.

The panel planned to work out a mid-term report on the issue in December and a final report would be due by summer 2012, local media reported.

The nuclear crisis at the crippled plant was the world's worst nuclear accident since the 1986 Chernobyl explosion. It was triggered by the devastating March 11 earthquake and ensuing tsunami.

It is still leaking radioactive substances into environment. And, the Japanese government and the plant's operator Tokyo Electric Power Co. are still battling to bring the facility under control.