Smokers at a Dorset police station have been pausing before lighting up since a family of blue tits took up residence in their cigarette butts bin.
The family of blue tits have chosen an unlikely home
Two adult birds and about 10 eggs are nestled in a metal bin attached to a wall outside Dorchester Policing Unit.
It is thought the family will remain there until June or July, police said.
The area around the bin has been cordoned off so the wild birds are not disturbed and fly the nest leaving their eggs, a police spokesman added.
Sgt Dave Stroud said: "It's incredible. There are two adult birds and about 10 eggs.
"We've taken advice from one of our wildlife officers and coned off the area so the birds don't get disturbed and leave the eggs.
"I suppose you could say it's a joint operation to stamp out smoking once and for all."
Officers have had to find alternative places to put out their cigarettes.
He believes the birds flew in on 6 May.
PC Dave Bird, wildlife officer, said: "All wild birds are protected in this country, especially during the nesting period.
"While they are building their nest, while the nest is in use and until all the birds leave the nest - probably in June or July - everything is being done to prevent them from flying the nest and leaving the eggs.
"We have put tape up, coned the area off and put a notice up warning people that there are birds nesting in the bin.
"The last thing the birds want is to be disturbed by lots of nosy police officers."