The Foreign Ministry confirmed on Wednesday that Chinese police have detained 35 Japanese nationals suspected of fraud.
Foreign Ministry spokesman Geng Shuang said in a daily news conference in Beijing that China informed Japan in accordance with the consular treaty between the two countries.
Earlier, Japanese news reports said the detentions were made in Fujian province.
Nikkei Asian Review said the suspects were detained after Japan's National Police Agency requested assistance and the case may have revealed the largest Japanese bank-transfer fraud group in China.
The suspects are accused of operating telephone scams targeting residents of Japan's Chiba prefecture, where victims were talked into transferring large sums of money via banks, it said.
It also said more groups have been calling from China to avoid being discovered and that it's up to the Chinese authorities to decide the disposition of the 35 people, as China and Japan don't have an extradition treaty.
It said the police departments of the two countries regularly hold working-level talks to address cases of fraud as well as issues such as cybercrime and terrorism.