Vacancies occurring otherwise than through the expiration of terms shall be filled for the unexpired terms. Members may be removed after public hearing, by the mayor, with the approval of the city council, for inefficiency, neglect of duty or malfeasance in office. Notice of the charge and pendency of the hearing with respect to the removal of a member of the planning commission shall be given by mail addressed to the residence of the accused member at least five days before the date of said hearing. The members shall be selected without respect to political affiliations and they shall serve without compensation; provided, however, they may be reimbursed for expenses necessarily incurred in performing their official duties.