Trained beekeepers had to tackle a 5,000-strong swarm of honeybees surrounding a central London store.
The insects were smoked out after gathering around a sign in front of a store in Victoria Street earlier.
Tony Mann, a trained beekeeper, said the bees were flying around the areas "like scouts".
The bees were moved to nearby Westminster Cathedral, where they will be looked after by beekeepers on the church's roof.
Mr Mann said: "We have either had a virgin Queen or an old Queen, she has left the nest and she has brought the swarm and settled on the shopfront."
He added that some of bees were flying around "like scouts to try to find out where the next best place to go is".
It is not known where the bees came from, but some shops in the area have their own hives.
David Beamont, from the Victoria Business Improvement District, said: "Local beekeepers were able to respond swiftly to manage the swarm, collect them in a mobile hive and move them to a suitable location."