Prosecutors searched the office of a pachinko chain operator in Tokyo on Thursday in connection with a bribery scandal involving a plan for a casino resort.

The pachinko chain had paid consultancy fees to an entertainment company set up by a former policy secretary to lawmaker Tsukasa Akimoto, sources familiar with the matter said.

Akimoto, a member of the House of Representatives, was arrested Wednesday on suspicion of accepting bribes from 500.com, a Chinese company that planned to open a casino resort in Japan.

The Tokyo District Public Prosecutor’s Office has already searched the homes of the former policy secretary and a former private secretary of Akimoto in relation to alleged cash smuggling by 500.com.

The former policy secretary set up the entertainment firm in 2011, the year after Akimoto lost his seat in the House of Councilors and became the firm’s representative director. The post was taken over by the other secretary.

Akimoto has been an adviser at the firm and received advisory fees.

After the secretaries’ houses were searched, Akimoto told reporters Dec. 9 that there had been no suspicious transfers of money to him.

The pachinko chain paid ¥200,000 in consultancy fees every month to the entertainment company for about two years until this autumn, the sources said.