A garage was destroyed and a house damaged by smoke as two DIY pest controllers attempted to burn a wasp nest.
The blaze took hold in a garage in Oakwood Drive, Bletchley at about 14:20 BST on Sunday.
Buckinghamshire Fire Service tweeted to urge people not to use fire to tackle wasp nests.
Both men were treated for smoke inhalation as four fire crews tackled the flames.
“We strongly advise people to contact a professional pest controller rather than try to do it themselves,” a fire service spokesman said.
“As far as I can tell, using fire to tackle a wasp nest is the number one thing not to do.”
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He added: “There were plenty of very angry wasps swarming around when we arrived.”
The spokesman said it was the second incident of its kind in the space of a month after a householder previously tried to set fire to a nest in a porch, which was damaged