Shady transfers of vast sums have been registered at a bank account held by a former sumo wrestler believed to be a go-between for wrestlers and mobsters involved in baseball gambling, investigative sources said Thursday.

The account records may be evidence of illegal gambling involving wrestlers and elders. The money transfers included what investigators suspect were payments of winnings for bets on professional baseball games, a source of income for the underworld.

The former sumo wrestler has identified a member of a Nagoya-based underworld group linked to Yamaguchi-gumi, the largest yakuza syndicate, as a bookie of the illegal gambling and told police the bookie "died about a year ago," the sources said, adding they are trying to verify this claim. Neither the wrestler, the bookie nor the bank were identified.