China expresses 'sadness' over fatal stabbing of Japanese schoolboy

China on Thursday expressed "regret and sadness" after a Japanese schoolboy who was stabbed in the southern city of Shenzhen died of his injuries.

"China expresses its regret and sadness that this kind of unfortunate incident occurred," foreign ministry spokesman Lin Jian said, adding: "We mourn the passing of the boy and express our condolences to his family."

Police in Shenzhen, Guangdong province, said a man had attacked a minor on Wednesday morning and the child was rushed to hospital. The suspect, a 44-year-old man, was seized, they said.

Lin told a regular press conference that the boy was a Japanese national whose parents are Japanese and Chinese citizens.

"After the attack, the boy was immediately rushed to hospital, and Guangdong authorities organized for some specialists to go all out to rescue him," he said.

"China will provide all necessary assistance to his parents in (handling) the aftermath (of his death)," Lin said, adding an investigation had been launched.

In June, a Japanese mother and child were injured in another knife attack in Suzhou near Shanghai, which China's foreign ministry described at the time as an "isolated incident".

Asked if this week's incident was also isolated, Lin said that according to "the current understanding of the situation, this is an individual case".

"Similar cases could happen in any country," he told reporters.

"China has always taken and will continue to take effective actions to ensure the safety of all foreign citizens in China."