Investigators have raided the offices of two major ad agencies, Hakuhodo and Tokyu Agency, over alleged bid-rigging involving test events for the Tokyo Olympics and Paralympics.
Tokyo prosecutors and the Japan Fair Trade Commission also searched two other firms on Monday.
The resumption of business travel between Japan and China is making travel agencies in China busy with inquiries from local businesses about trips to Japan.
On Monday, the two countries eased entry restrictions imposed in response to the coronavirus pandemic, allowing businesspeople to make trips for both short- and long-term stays. This will allow for business activities on a limited scope even during a 14-day quarantine period.
Japanese financial companies are moving to stop investing in or financing coal-fired power stations, in an effort to help reduce greenhouse gas emissions.
A major non-life insurance company, Sompo Japan Insurance, plans to end investment and financing for the construction of new fossil fuel power plants, which are inefficient and emit large amounts of carbon dioxide.
A group of European companies operating in Japan has called on the Japanese government to ease travel restrictions with Europe as soon as possible.
Michael Mroczek, the Chairman of the European Business Council in Japan, was speaking at a news conference in Tokyo on Monday.
Businesses across Japan are slowly reopening even before the government makes its final decision on lifting a nationwide state of emergency.
More than half the country's prefectures are likely to ease restrictions put in place last month.
Some prefectures in Japan are resuming business as the government mulls lifting the state of emergency due to the coronavirus before the end of the month.
More than 30 prefectures are expected to have restrictions eased while Tokyo is likely to stay under the emergency declaration.
Japan has stepped up efforts to reduce person-to-person contact by 80 percent in a bid to contain the coronavirus outbreak.
Economic Revitalization Minister Nishimura Yasutoshi on Thursday issued guidelines on what kind of steps governors can take to get business owners that continue to ignore government requests to suspend their operations.
The Tokyo Metropolitan Government plans to request the closure of entertainment facilities if the prime minister declares a state of emergency based on a coronavirus-related law.
The declaration would allow governors of designated prefectures to take various measures to fight the virus.
The Japanese government is studying additional measures to prop up the tourist industry and smaller businesses hit hard by the coronavirus scare.
Officials have already come up with a 140-million dollar package to fight the outbreak.