China has arrested two Japanese for spying, the Foreign Ministry said on Wednesday, and Japan said the two had been held since May and diplomats were doing all they could to help.
Japan's Asahi newspaper said the two men were from the private sector. One was taken into custody in China's northeast province of Liaoning near the border with North Korea and the other in the eastern province of Zhejiang near a military facility, the paper said.
The newspaper added China appeared to be looking into whether the men were acting under instructions from the Japanese government.
Chinese Foreign Ministry spokesman Hong Lei told a daily news briefing that "relevant authorities" had arrested the two "in accordance with the law for engaging in espionage activities in China".
"China has already notified the Japanese side of the relevant situation," he added, without elaborating.
Japanese Chief Cabinet Secretary Yoshihide Suga confirmed that two Japanese had been in custody since May but declined to give any further details.
"Diplomats are taking all appropriate steps and providing all possible assistance," he said, declining to give any details.
Asked about reports that a third was being held, he said the government was only aware of two.
Speaking earlier in the day, Suga said: "Our country is certainly not doing such things. I would like to say that this is the same with regard to all countries."
Chinese President Xi Jinping has overseen a tightening of already strict security laws and regulations, including setting up a new national security commission and renaming the national security law, which took effect in 1993, as the Counterespionage Law.
In 2010, four Japanese nationals were temporarily detained in China on suspicion of entering a military zone and taking photographs without permission. The detentions came at a time of escalating tensions between Tokyo and Beijing.
Last year, China's then-ambassador to Iceland disappeared following reports he had been arrested by state security for passing state secrets for Japan. China has never explained what happened to him.
Sino-Japanese relations, colored by Japan's occupation of parts of China before and during World War Two, have thawed since Prime Minister Shinzo Abe met Xi twice since last November.
