Ibaraki had the most undocumented foreign workers in Japan for four years.

Foreign workers are important to Japan due to workforce shortages.

People can report suspected illegal employment on the prefecture's website, but must provide personal information and identification.

In 2025, 13,435 foreigners were caught working illegally in Japan.

The prefectural government announced the policy to improve public safety.

The measure has been criticized for potentially encouraging discrimination.

Opposition groups protested the scheme, saying it could foster suspicion toward migrants.

Japan had 2.6 million foreign workers in October 2025, a record high.

Most foreign workers in Japan have specialized or technical professions.

Vietnamese workers are the largest foreign workforce in Japan.

Chinese workers are the second-largest foreign workforce in Japan.