Police questioned Rokkasho Mayor Hisashi Hashimoto on Thursday on suspicion of accepting 4 million yen in bribes from a local businessman in return for information on bids submitted for public works projects.
Investigators said they are looking to arrest Hashimoto once they acquire sufficient evidence to back their case.
Hashimoto, 54, allegedly received 1 million yen in cash on four occasions from Osamu Kosaka, 60, former president of Aomori firm Ou Denki Kogyo, in return for information on bidding prices submitted for public work projects in the village of Rokkasho.
Kosaka gave Hashimoto the cash in half-year intervals beginning in June 1998, according to the police.
Kosaka, currently being tried in a separate bribery case, implicated Hashimoto during police questioning.
During a news conference on May 8, Hashimoto denied that he had received any money from Kosaka or that he had done anything illegal.
Ou Denki Kogyo, based in the town of Noheji, near Rokkasho, has won at least four public tenders held by the Rokkasho village government since November 1998. The contracts were worth a total of 90 million yen.
Hashimoto was first elected Rokkasho mayor in 1997 and won a second four-year term in November.
Several nuclear fuel cycle facilities are located in Rokkasho, a coastal village in northern Aomori Prefecture.