Swarms of Asian “super ants” gnawed through electric cables when they formed a colony at a home in Hendon.
The family living in the house were disgusted when they noticed hundreds of the tiny black creatures crawling inside their microwave, their beds and across surfaces.
Pest control agency Clean Kill was called to investigate – but soon realised it was not a “normal” job when the ants were not killed by normal pesticides.
Also known as the fire ant, the insects were first identified in Britain in 2009 in Gloucestershire but are usually found in Asian countries.
Chris David, technical manager for the firm, said: “They were everywhere and it was strange as we just couldn’t seem to kill them off.
“It was strange. It took us three weeks to be certain this was in fact the Asian super ant but because we’ve never had to deal with something like this before, we’ve had to learn quickly.
“Some of them are microscopic so it came as a total surprise to the family, who had no idea what they were.”
Although they cannot chew, the ants – which do not fly – are mainly attracted to electric cables, which means they can cause fires.
It took six sessions for Clean Kill to permanently exterminate the pests from the family household.
For now, how they made their way from Asia to Hendon remains a mystery.
Mr David added: “People don’t need to worry as we think it’s an isolated case. Fingers crossed they don’t spread.
“If one gets on your skin, it’s not going to bite or sting you. It just might feel a bit unpleasant.
“Luckily, we think they are under control now.”