It shall be the duty of the sheriff in each county to provide security for the ballot boxes or transfer cases from the time the ballot boxes or transfer cases are stored by the county election board following an election until the election results have been certified or, in the event a recount contest is filed, until such time as the ballot boxes or transfer cases are delivered to the district courtroom. Provided, ballot boxes or transfer cases may be returned to the custody of the secretary of the county election board for the purpose of conducting a post-election audit as described in Section 1 of this act.¹