A day after the accident at the Fukushima No. 1 nuclear power plant was raised to the level of Chernobyl, Tokyo Electric Power Co. President Masataka Shimizu offered apologies but was unable to outline specific ideas or plans to stabilize the situation.

"Again, we deeply apologize to residents around the plant and Fukushima Prefecture, our customers, shareholders and people in society for causing concern and trouble," Shimizu said Wednesday at a news conference at company headquarters in Tokyo's Chiyoda Ward.

Based on the International Nuclear Event Scale devised by the International Atomic Energy Agency, the Nuclear and Industrial Safety Agency, the government's industry watchdog, raised the level from 5 to 7, considered a "major accident," on Tuesday, based on the amount of radioactive material emitted.