TOKYO -- China has arrested two Japanese citizens on spying allegations, officials said Wednesday.

Japanese Chief Cabinet Spokesman Yoshihide Suga told reporters that the two were picked up in May, one in Zhejiang province and the other in Liaoning. China said the two face spying allegations.

Suga said that the Japanese government knew about the arrests soon after the two were detained, but withheld the information.

He refused to give details on the arrests, including the specific allegations the two face. Earlier, Suga said that the Japanese government "absolutely (does) no such thing," referring to sending spies to other countries.

China's government said authorities arrested the two on suspicion of spying.

"The legal basis of the arrests is that these two people engaged in spying in China," Chinese Foreign Ministry spokesman Hong Lei said at a regular briefing Wednesday in Beijing. "If there's anything in common for these two people, it's that both of them engaged in spying in China."

Japanese newspapers and television stations reported earlier that the two were both men. One was apprehended near military facilities in coastal Zhejiang, and the other near the border with North Korea at about the same time, according to the reports, which cited unnamed sources familiar with Japan-China affairs.

In 2010, four employees of a Japanese construction company were accused of filming a Chinese military site in Hebei province but were released within a few weeks.