An Asian hornet has been found north of the Mendip Hills in North Somerset.
The species have to be destroyed because they attack and kill native honey bees by biting their heads off.
A three mile surveillance zone has been set up and work to identify, destroy and remove any nests is underway.
The first confirmed sighting took place near Tetbury in Gloucestershire, last month.
The nest was found at the top of a 55 foot tall conifer tree. Inspectors from the National Bee Unit are continuing to monitor the area for Asian hornets alongside local beekeepers. However to date, no live hornets have been seen since the nest was removed.
The Asian hornet (Vespa velutina) can grow up to 2.5cm (one inch) long.
It arrived in France in 2004 and is now common across large areas of Europe. It was discovered for the first time in Jersey and Alderney this summer.
How to spot an Asian hornet:
Slightly smaller than native hornet
Dark abdomen, 4th segment yellow
Bright yellow tips to legs
Entirely brown or black thorax
Most likely to be seen close to bee hives
We have been anticipating the arrival of the Asian hornet for some years and are implementing our well-established protocol to eradicate them and control their spread. It is important to remember they pose no greater risk to human health than a bee, though we recognise the damage they can cause to honey bee colonies. That’s why we are taking swift and robust action to identify and destroy any nests. We remain vigilant across the country, working closely with the National Bee Unit and their nationwide network of bee inspectors.