An air rifle was found by two boys in bushes close to Maino Crescent in Lutterworth on Monday.
It was reported as a shotgun but was actually an air rifle reported stolen in December.
PC Paul Williams said: “The children did exactly the right thing when they found the air rifle.
“They didn’t touch it and alerted an adult who called the police.
“The rifle might have been loaded and it could have culminated in a nasty accident.”