Japan's nuclear regulators have pointed out that a lack of human involvement in efforts to safeguard nuclear material led to serious security lapses at the Kashiwazaki-Kariwa power plant in Niigata Prefecture, central Japan.

All seven of the plant's reactors are currently offline due to government policy following the 2011 Fukushima nuclear accident. The plant's operator, Tokyo Electric Power Company, hopes to restart the facility but cannot unless the problems are judged to have been resolved.

A senior Russian official has said that an exercise between Japan Self-Defense Forces and the US military near the Russian border is a threat to Russian security.

Russian Deputy Foreign Minister Igor Morgulov spoke in an interview with Russia's state-run RIA news agency on Tuesday.

The Japan Coast Guard is braving bad weather and sea conditions in search of passengers and crew of a tour boat that went missing off Hokkaido, northern Japan.

The boat, named "KAZU I," went missing on Saturday during a cruise along the Shiretoko Peninsula, a UNESCO World Heritage site.

The Japanese Defense Ministry reports that a Chinese naval vessel entered Japan's territorial waters off the southwestern prefecture of Kagoshima.

Defense officials say a Chinese survey ship was spotted in Japan's contiguous zone west of Kuchinoerabu Island at around 8:30 p.m. on Tuesday. They say the vessel entered Japanese territorial waters at about 11:00 p.m.

Japanese Prime Minister Kishida Fumio has told Ukrainian President Volodymyr Zelenskyy that Japan will provide additional supplies to Ukraine, including food and medicine.

Kishida conveyed the pledge to Zelenskyy by telephone on Tuesday evening, Japan time. This is their fourth such conversation.

Those engaged in the effort to recover 15 missing people have little to show for their effort four days after a tour boat sailing off the northern Japanese prefecture of Hokkaido apparently sank in bad weather.

The boat, named Kazu One, went missing on Saturday during a cruise along the Shiretoko Peninsula.

Japanese Prime Minister Kishida Fumio said the government has approved an emergency package to cope with soaring prices as the Ukrainian crisis fuels global inflation.

Kishida said the government must prevent high prices of crude oil and other items such as grains from hampering Japan's recovery from the coronavirus pandemic.

The Tokyo Metropolitan Government reported 5,048 new coronavirus infections on Tuesday.

The figure is down about 500 from a week ago.

Radio exchanges between the captain of the tour boat that went missing off the northern prefecture of Hokkaido and another tour vessel operator suggest the boat faced an increasingly dire situation.

A source revealed that the operator of the missing boat, Kazu One, had its radio antenna broken several months ago. The captain, Toyoda Noriyuki, was therefore communicating by radio with the other operator.

The Bank of Japan said it will continue to conduct unlimited buying operations of Japanese government bonds, aimed at keeping long-term interest rates from rising.

The BOJ said it carried out these operations at a fixed yield of 0.25 percent in the four business days through Tuesday. It said it bought 10-year JGBs worth just over 2 trillion yen, or about 16 billion dollars, in the four-day period.

A state minister of Japan's transport and tourism has strongly demanded that the operator of a tour boat which sank off the northern prefecture of Hokkaido provide a full explanation to concerned families about the accident.

The boat, named Kazu One, went missing on Saturday during a cruise along the Shiretoko Peninsula. It was carrying 26 passengers and crew members. Eleven have been confirmed dead, and the remaining 15 are still missing.

A low pressure system and a rain front are bringing rain clouds to western Japan along the Sea of Japan coast.

Japan's Meteorological Agency says torrential rains will likely fall through Wednesday in a wide area ranging from the southwestern region of Kyushu to the Tohoku region in the northeast.

The Japan Coast Guard continued its rescue mission on Tuesday, after a tour boat disappeared off the coast of the northern island Hokkaido at the weekend.

The boat, called Kazu One, was carrying 26 passengers and crew members on Saturday when it went missing in rough waters around the Shiretoko Peninsula in northeastern Hokkaido.

Japan's health ministry has decided to approve Pfizer and Moderna vaccines for use in providing a fourth coronavirus inoculation.

The decision was made on Monday at a meeting of an expert panel convened by the ministry.