Banks in several countries have been hit by a new form of financial cyberattack, in which a virus alters banks' computer systems to allow cash withdrawals from automated teller machines to users without an account, Interpol officials said Saturday.

Interpol, or the International Criminal Police Organization, warned that although no incidents have yet been reported in Japan, the cyberattack method is likely to spread to the country before long, and that Japanese banks should start taking sufficient precautions.

According to Moscow-based information security firm Kaspersky Lab, the virus has been found in about 100 financial institutions in 30 countries, including the United States, Germany and China, since 2013. It is linked to losses of over ¥100 billion ($832 million) globally.

While previous cyberattacks have targeted bank customers' computers to gain access to their accounts, the new method directly attacks banking systems to allow ATM withdrawals from dummy accounts.

Interpol is working with authorities in affected countries to tackle the virus. The organization has set up a dedicated center to deal with new developments in cybercrime, the Interpol Global Complex for Innovation, in Singapore.

On Friday, Tokyo police said about 82,000 personal computers worldwide, including about 44,000 in Japan, have been found infected with a separate virus that steals online banking users' login details to make unauthorized money transfers.