Japan’s prime minister has demanded an explanation from Beijing over the fatal stabbing of a schoolboy in the second knife attack on Japanese children in China in months.

While the motivation of the assailant remained unclear, Japanese officials have urged increased security around Japanese schools in China.

Japan's ambassador to Beijing has asked for more security for Japanese nationals in China after a 10-year-old Japanese boy was killed this week in a knife attack that was the second to target school students.

A 10-year-old Japanese student was stabbed near his school in Shenzhen, China, and has died, officials said, despite Tokyo's requests for enhanced safety.

Some Japanese companies in China have offered to send their staff and their families back home after a 10-year-old Japanese boy was fatally stabbed in the Chinese city of Shenzhen, a Japanese executive and employees of Japanese firms in Beijing said on Friday.

In a call with China’s vice-foreign minister Sun Weidong on Thursday, Japan’s ambassador Kenji Kanasugi “strongly urged” Beijing to share detailed information about the incident, which was the second targeted attack on Japanese schoolchildren in China in recent months.

The killing of a Japanese schoolboy in the Chinese city of Shenzhen has sparked worry among Japanese expats living in China, with top firms warning their workers to be vigilant. Toshiba and Toyota have told their staff to take precautions against any possible violence,

The attack on the 10-year-old boy was the second such incident in months amid a social-media campaign that has stirred up anti-Japan sentiment in China.