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.

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.

Few details have been made available about the attack. The 10-year-old victim, who was identified by the surname Shen in a local police statement, was stabbed by a middle-aged man on Wednesday while walking to a Japanese school in China’s southern tech hub of Shenzhen. He died the following day while undergoing surgery.