A temporary staff agency gave 13 million yen in cash in 1997 to an unidentified person with close links to Takanori Sakai, it was learned Saturday.

The money, meant as a "reward," found its way to the arrested lawmaker through a middleman, according to sources close to the case.

The money was not part of the 120 million yen in political donations that the House of Representatives member and his secretaries failed to declare, they said.