A Christchurch resident has described being herded out of his family's Avonhead home by armed police amidst a stand-off next-door

Police have cordoned off Beatrice Place, as they try to negotiate with an armed person holed up inside a home and understood to be alone.

The stalemate has been ongoing for hours, and armed police began evacuating neighbours shortly after 7 this evening.

One resident says they had only a few minutes to grab clothing and phones before being escorted to the end of the street to be picked up by family.

He says his boys are probably young enough not to understand what's going on, but it's fairly traumatic.