Tokyo police have arrested four people on suspicion of illegally arranging cleaning jobs for Indonesians admitted to Japan as agricultural workers.

Those arrested by the Tokyo Metropolitan Police Department include Hihara Tatsuhito, the president of a temporary staffing company in Yamanashi Prefecture, central Japan. Kobayashi Kansei, an executive of a laundry plant, was also arrested.

The police say the four are suspected of violating the immigration control law by arranging jobs at the plant for three Indonesians from last October through June. The three have residency status as specified skilled agricultural workers.

Investigators say Hihara partially denied the allegation, saying he believed they could legally work in an industrial laundry if there were no agricultural jobs.

Kobayashi is said to have admitted to the allegation. He was quoted as saying he had no choice but to use the workers to cover serious staff shortages, adding that he wanted to keep the business running.

Police suspect that Hihara’s company illegally dispatched about 120 foreigners to the same plant during a period of over two years through June.