I am a manager in a small insurance company. I have been with the company for over 2 years and have my own department and 3 direct reports (one of them is new and not really involved in the problem). They are all female and around the same age in their early 20's. I am a few years older than them.
The office is set up in cubicles and the demographic of employees is largely in their early to mid 20's. I've noticed that a few of the young male employees (not my direct reports) like to come over to flirt and chit chat with my female employees frequently throughout the day. I know they have also been sending my employees emails with funny content and they prove to be a huge distraction to their concentration.
At one point I know the issue had escalated to upper management and HR investigating the content of the emails to check for inappropriate content. For the most part they were 'harmless', however there apparently were a few instances of unkind things being said about other employees here (including myself).
The individual mostly responsible for instigating the email traffic (one of the male employees) was spoken to by their manager and I had hoped the issue would be resolved after that. Over the last week or so I've noticed that the culprit is at it again and I've gone directly to their manager (we'll call him John) to let him know it is effecting my employees now as well. I told John that I am happy to work out a solution with him so this can be stopped and so our employees know this behavior is unacceptable.
I am not sure how to bring this up with my employees as they never seexm to initiate the emails. Because we are close in age I have had issues in the past with my employees not taking me seriously and I fear that may be the case if I speak to them about this matter. Does anyone have advice on how I should approach my two employees about their behavior?