A fire broke out at a nuclear power plant in Japan's Miyagi Prefecture following a powerful earthquake that hit northeastern Japan while authorities have detected no abnormalities such as radiation leakage at nuclear plants, latest reports from the Mainichi Daily News says.

The International Atomic Energy Agency is scrambling for details from contacts with Japan's industry ministry, while saying in a statement that at least four nuclear power plants closest to the quake have been safely shut down after the 2:46 p.m. quake, the report said.

According to the ministry, a total of 11 nuclear reactors were automatically shut down at the Onagawa plant, Fukushima No. 1 and No. 2 plants and Tokai No. 2 plant after the biggest-magnitude quake in the country's modern history.

However, the ministry said there were no immediate reports from monitoring posts of fires or other abnormalities near the nuclear plants.

Tokyo Electric Power Co. reported an abnormality at its Fukushima No. 1 nuclear plant, saying the system to cool reactor cores in case of emergency stopped at the No. 1 and No. 2 reactors.

Water spilled from pools containing fuel rods at the Kashiwazaki-Kariwa plant on the Sea of Japan coast in Niigata Prefecture and the Onagawa plant, the operators said, saying they saw no signs suggesting radiation leaks, report added.

Japanese Prime Minister Naoto Kan told a press conference, Parts of nuclear plants were automatically shut down but we haven't confirmed any effects induced by radioactive materials outside the facilities.