Tokyo police have arrested 23 men for allegedly pimping out female workers at sex entertainment stores — the largest number of arrests in a single crackdown.

Masaki Tooka, a 51-year-old company executive from the city of Fukuoka, and 22 others were arrested in violation of the anti-prostitution law, the Metropolitan Police Department said.

Tooka and 10 others have owned up to the charges while the remaining 12 have denied them.

According to investigators, a group involving Tooka had operated four such outlets in Tokyo, including in Gotanda and Shimbashi districts, dispatching female workers to clients at the location of their choosing. It had been raking in at least ¥1.2 billion ($7.6 million) annually in sales.

The group operated by constantly changing the names of its outlets. Of the 23 arrested, police determined Tooka and another individual to be supervisors of the operation while three were store managers. The other 18 were their employees.

Tooka was arrested on suspicion of dispatching women in their 20s to have sex with three male clients in their 40s and 50s at a hotel in Tokyo’s Shinagawa Ward between April and May.

Police first became aware of the group last year when they arrested a woman in Shinjuku Ward's Kabukicho district who had been waiting for a client to have sex with. The woman told investigators that she was working at an outlet operated by Tooka.

Translated by The Japan Times