Bacon drives squirrels nuts.
Bacon makes squirrels attack people
Officials at the University of Greenwich in London have put up a sign warning staff not to feed the breakfast treat to the rodents as it makes them attack people.
The notice reads: "Please could staff not feed bacon to the squirrels as they have now started attacking pedestrians."
The warning has gone viral and has prompted experts to consider why bacon has such a dramatic effect on the animals.
One suggested that the "fat and sodium in bacon are too much for the squirrels' systems" and can cause organ problems.
The incident has led to much amusement on social media as one user has dubbed the animals as the "Bacon battalion".
Another wrote: "Pedestrians taste of bacon? Is anyone going to test this theory?"
A third observed: "The invasion has begun!! They've been right under our nose this whole time, biding time, waiting for civil instability amongst the humans."