A major incident is ongoing in Muswellbrook, with police, firefighters and the riot squad on the scene.
Negotiators have been speaking with an individual at a home on Parkinson Avenue, with the stand-off now lasting for over 14 hours.
Police have been using a megaphone to speak with the resident, and have made it clear that they will not be leaving until the situation is resolved.
It’s believed the occupant of the home is alone, but may be armed and a danger to police, the community, and themselves.
A NSW Police spokesperson says that the street remains closed and residents are urged to avoid the area.

