The editor may or may not inform the department or the institutional head of the author about the plagiarism. On the other hand if the plagiarism is caught after the paper is published, it means that the facts are now in public domain. The editor will retract the paper and publish a retraction in subsequent issues of the journal. This information will also be sent to the institutions head asking for disciplinary action against the authors. If authors have used financial resources of the institution to write this paper, it would result in a criminal investigation.
