The city treasurer of a city of the first class shall keep all money in his or her hands belonging to the city separate and distinct from his or her own money. He or she is expressly prohibited from using, either directly or indirectly, the city money or warrants in his or her custody and keeping for his or her own use and benefit or that of any other person. Any violation of this section shall subject him or her to immediate removal from office by the city council, and the council may declare such office vacant. The mayor shall appoint a successor, who shall be confirmed by the city council, to hold office for the remainder of the term.