Dai-Ichi Kangyo Bank officials wined and dined Finance Ministry officials while the bank was under a ministry investigation in 1994, and they are suspected of prodding the ministry into issuing a favorable report on its bad loans, sources said Wednesday.

The Tokyo District Public Prosecutor's Office said it is investigating details of the entertainment and the inspections. Dai-Ichi Kangyo is suspected of entertaining the inspectors in exchange for a favorable classification of its bad loans.

Loans by financial institutions are classified according to repayment prospects. Healthy loans are put in the first category; those in danger of becoming delinquent in the second; at serious risk of delinquency in the third; and unrecoverable loans are put fourth, they said.