What is the ruling on disposing of money of unknown origin and the suspicious increase from usury, knowing that the principal is known?

Bank deposits are loans, and the interest paid on them is prohibited usury (riba), unlawful money that a Muslim is not permitted to benefit from, neither for himself nor for anyone he supports. It must be spent on public welfare for Muslims, such as schools and hospitals. This is not considered charity but rather a purification from unlawful gain. You must ascertain the amount of usurious money by referring to the bank's system and your parents. If you determine the amount, it is obligatory to disburse it for the general welfare of Muslims; otherwise, rely on your best judgment.