When conflict arises, you need to raise the issue with the parties involved. 
Emphasize the need for your employees to address it. Explain that negative feelings and thoughts can be handled in an appropriate manner that can actually make them positive and productive.

Speak with each party separately to gain their perspective on what the tension is all about. 

Make sure that along with any emotional information, you discuss specific facts or events that led up to or inflamed the situation.

Allow them to share their version of the events or issues. 

Often, this step will elicit issues or facts that the other party was unaware of.

Each side has some concern the other party can agree with, and this will become the foundation that enables you to bridge the gap that separates the parties involved.

For the sake of working together, each person must be willing to give in a little. 

This step may take a while because the sides are already firmly entrenched in their own viewpoint or version of what should happen to resolve the issue. 

The feelings and thoughts that arose during the conflict stage have to be worked out. 

Unless this happens to everyone's satisfaction, the problem may go away for the moment, but the hard feelings or thoughts will persist, and then a repeat conflict might occur.

Resolve to address future conflicts in a positive manner. 

The model, of course, would be similar to how this one is being resolved.