If the loan cannot be repaid at maturity, the bank will auction the mortgaged house, pay the loan principal and interest in arrears with the proceeds from the auction, and the rest will belong to the mortgagee (the owner of the house); If it is insufficient, the bank will continue to recover the remaining loan principal and interest from the borrower.

This is a debt dispute, and there is generally no problem of violating the criminal law. Unless the borrower takes illegal measures to the extent of violating the criminal law.