A Japanese-Brazilian woman allegedly involved in the murder of a former classmate in Osaka in 2014 was extradited Wednesday from China, where she had been held after fleeing from Japan.

Japanese police arrested Oishi Ketty Yuri, 32, aboard a flight from China. Oishi is only the second person extradited to Japan from China, with which Japan has no extradition treaty, according to the National Police Agency.

Oishi is suspected of killing Rika Okada, a 29-year-old nurse and her former classmate in elementary and junior high school, at Okada's home in the city of Osaka in late March 2014 before stealing her bag, according to investigative sources.

But Wednesday's arrest concerned the allegation that Oishi illegally used Okada's credit card. Police plan to serve a fresh arrest warrant on her on murder-robbery charges.

Okada went missing in late March 2014. Her body was found at a rental storage space in Hachioji in western Tokyo, in May that year, with about 50 stab wounds and scars, the sources said. Oishi was living in Hachioji at the time.

Meanwhile, Oishi traveled from Japan to China in May before Okada's body was found, using a passport bearing her former classmate's name, and was subsequently detained by Chinese authorities for suspected illegal entry into China, according to the sources.

Facing lack of an extradition pact between Tokyo and Beijing, the Osaka police requested via a diplomatic channel that China hand her over.

China's supreme court ruled last year that Oishi should be transferred to Japan.