A storage container, comprising a rigid body including a floor, a front wall, a back wall, and side walls, at least one separating wall, and a plurality of fixing elements for removably fixing the separating walls to the storage container. The storage container further comprises a locking element. The container further comprises a plurality of compartments configured to be separated by the separating wall and locked via the locking element. Further, a system comprising a mobile robot and the storage container is disclosed. Also disclosed is a method for secure package delivery employing the system.