Except for investments authorized by subdivision 4-5-6(c), all investments made pursuant to §§ 4-5-5, 4-5-6, 4-5-8, 4-5-23, and 4-5-28 shall be in the physical custody of the political subdivision or may be deposited in a safekeeping account with any bank or trust company designated by the political subdivision as its fiscal agent. The interest earned shall be credited to the respective fund or the general fund.
SDCL 4-5-9