It would be the DLTF command (DLTOBJ is not a valid IBM command), and yes you can. However, you just want to make sure to not delete them out of sequence. If you have something like:
then you wouldn’t want to delete
without adding what came prior as well. doing that will interrupt the link in the history log and could cause your system to halt because it will not be able to write data to the history log, which will prevent new jobs from entering the system and also keep currently running jobs from completing successfully.