The five members to be selected from the Fire Department shall be elected biennially on the last Monday in June by secret ballot of the active members of the said Fire Department eligible for participation in the fund established under this Part. The first election shall be held within fifteen days July 27, 1966 and biennially thereafter, as above provided. In the event a vacancy should occur in the said board of trustees among the members of the said board from the ranks of the said Fire Department, a special election shall be called by the said board within sixty days after the occurrence of such vacancy.
La. Consolidated Public Retirement § 11:3464