The insects, which feast on bees and possess a potentially deadly sting, have been spotted on the Channel Islands for the first time this year.
The sighting of the world’s largest species of hornet has stoked fears that the pesky insects will cross into the UK over the coming weeks.
Native to south-east Asia, Asian hornets were first spotted in the UK in 2016.
They are able to kill people with allergies with just one sting, while they also pose a threat to the environment and native species – with one hornet being able to eat 50 bees in a day.
Experts have warned that the environmental damage caused by Asian Hornets in the UK could amount to over £7.6 million a year.
However, there are several ways to deal with large swarms, including destroying their nests and trapping the insects with bait.
Liam Tickner, Garden and Outdoor Living Category Manager at OnBuy, said: “At this time of year, flies, gnats, and wasps increasingly become an annoying part of our lives.
“Moving into summer, as we open our doors and windows, plus spend more time outside, we are increasingly exposed to flying pests.
“In addition to this, with reports that killer hornets are set to flood the nation in the coming weeks, it seems people have decided to prepare themselves."
Sales of insect swatters have skyrocketed this week, according to latest data.