Japan's government says it's building a computer database of registered private lodgings. It aims to stop people renting out properties illegally in the rush to cash in on the growing number of tourists visiting Japan.

A new law that took effect last June requires people to notify municipalities if they want to rent out their homes for short-term stays.

But the Tourism Agency says 16 percent out of more than 40,000 properties listed on major private-lodging websites at the end of September were not registered or didn't meet requirements.

Officials say they will complete the database next month, and share it with the websites so they can screen out any illegal listings.