A 15-year-old boy from Formby in Merseyside has been arrested on suspicion of importation of a firearm.
As part of their investigation police say they recovered a handgun which had been ordered from the United States and was destined for delivery to a property in Formby.
"Working together with UK Border Force we were able to stop the weapon from reaching its final destination. Our message to those involved in gun crime is clear, we are relentless in our pursuit of those who use firearms on our streets."
The boy has been questioned and released on police bail pending further inquiries.
More top news
A selection of your July images at dusk and dawn
The longest, continuous, inflatable obstacle course in the world is bouncing into Merseyside this weekend.
Jose Mourinho insists Manchester United's hectic-looking pre-season schedule will help rather than hinder.