A former Japan Dental Association chairman tied to an embezzlement scandal sent a 100 million yen check from the coffers of the group's political arm to former Prime Minister Ryutaro Hashimoto prior to the 2001 House of Councilors election, investigative sources said Thursday.

The check is viewed as a political donation from the association's political group to Hashimoto's faction in the Liberal Democratic Party, though the money was not listed in the political funding reports of either side, the sources said.

Prosecutors have launched an investigation into this alleged violation of the Political Funds Control Law.