The Tokyo Immigration Bureau has detained seven foreigners, including three professional boxers from the Philippines, for allegedly working at factories and farms in Ibaraki Prefecture without proper visas.

Among the boxers was Manuel Melchor, 28, who for five months in 1992 held the International Boxing Federation title in the straw-weight division. According to a bureau official, Melchor and the other boxers came to Japan last November at the invitation of local agents to compete in bouts in Chiyokawa, Yuuki-gun, Ibaraki Prefecture.

In April, the boxers began working illegally, believing they could earn more money as laborers or farmers, the official alleged. Melchor fought two matches, earning 500,000 yen per match.