Is it permissible to use bank interest to pay off a poor mother's debt, or to help needy and impoverished siblings?

Usurious gains are illicit money that must be disposed of by spending it on general Muslim welfare projects or giving it to the poor and needy. A person is permitted to use it to pay off his mother's debt if she is unable to do so, or to give it to his two needy brothers, with the intention of getting rid of illicit money, not as charity.