Householders have been warned to keep an eye out for uninvited creepy crawlies, as a new generation of tropical ants makes its way to south east London and north Kent.

Pest experts say species from all over the world are now establishing big colonies in Britan.

The new inhabitants include ghost, crazy and big-headed ants which could post a risk to public health, according to pest control register Basis Prompt.

Some of the unwelcome cretins will bite or sting and they can carry a wide range of disease organisms such as streptococcus and salmonella, which makes them particularly dangerous if they contaminate food.

Pest control expert David Cross, from Basis Prompt, said most of the new ants have arrived here via container ships from different parts of the world, either in food or soft furnishings.

He said: "Species like these were once contained to their own parts of the world, but they now seem to be on something of a world tour.

"The population of tropical ants is this country is certainly growing all the time and we’re now seeing many more problems with colonies of certain species than we have witnessed in the past."

Multiple-occupany buildings such as blocks of flats and hotels or institutions such as hospitals or prisons, provide the perfect living conditions for tropical ants.

He added: "Most tropical ants can’t live outside and need warmth to survive so they can thrive in places where heating is on all the time

"They’ll generally head to areas where food is manufactured or prepared, which is why food producers and restaurants are at risk too."

As well as being a danger to the public, tropical ants can be particularly difficult to get rid off, because colonies can contain up to 200 queens.

Have you spotted a new tropical ant? Get in touch at jessica.bell@london.newsquest.co.uk.