According to Sherif's office, its a mental subject/barricade situation. Does not appear to involve anyone else. https://www.facebook.com/492782070761280/posts/4289625801076869/
Text from the facebook post:
Atoka Road at John S. Mosby Highway will be shut down for an undetermined amount of time. There will be an increased Law Enforcement presence in this area as well. Please try to avoid the area if possible and use an alternate route of travel. Thank You.