Beijing has said an increase in hate crimes targeting Chinese citizens and institutions in Japan must be met with concrete security measures by authorities in Tokyo.

Speaking at a regular press briefing on Wednesday, Foreign Ministry spokeswoman Mao Ning urged the Japanese government to take China's concerns seriously.

Mao pointed out that, last week, Japanese police arrested five suspects in connection with assaults against Chinese citizens.

Mao added that there has been a surge of extreme and threatening anti-China remarks appearing on Japanese social media networks.

In recent days, members of staff at the Chinese embassy and consulates in Japan have also faced repeated harassment by right-wing groups, both online and in person.