A restaurant in the city of Nagasaki sold discount sashimi rice bowls using fish caught by an organized crime group’s illegal poaching operation, local police said Tuesday.

The eatery in front of Nagasaki Station, which recently shut down, was popular among tourists and workers for dishes including a ¥500 seafood rice bowl.

It was run by a relative of a senior figure in the yakuza group and its annual sales had reached ¥30 million, the police added.

The crime boss and other members of the syndicate have been indicted for poaching in waters off Nagasaki from around 2016. Investigators later discovered they had supplied fish such as red sea bream to the restaurant.

The gang borrowed scuba diving gear in Nagasaki. Some members were designated to do the fishing and others to drive the boats or serve as lookouts, according to the police.

Investigators found about 200 kilograms of vacuum-packed frozen fish fillets that were bound for the restaurant during a raid at an information center in the city’s downtown adult entertainment district. The center was under the control of the yakuza group’s boss, the police said.

“I went to the restaurant a few times because it was cheap, but I never imagined an organized crime group was involved,” a businessman in his 20s said.

As a 1992 law targeting organized crime has led to a crackdown on many types of illegal businesses for gangsters, poaching may have become the group’s source of income, the police said.