Police have seized components for what could be the UK's first ever 3D-printed gun in what they called a "really significant discovery".

Greater Manchester police said they believed the parts represented the next generation of firearms, which could be created by gangs in the privacy of their homes and smuggled with ease because they could avoid X-ray detection.

The gun parts were discovered, along with a 3D printer, when officers executed warrants in the Baguley area of the city on Thursday.

Officers found what were thought to be a plastic magazine and trigger which could be fitted together to make a viable gun. They said the haul also included a quantity of gunpowder.

The parts are now being forensically examined by firearms specialists to establish if they could construct a working device. If so, it would be the first seizure of its kind in the UK, police said.

Suspected 3D gun component parts found in Manchester police raid. Photograph: Greater Manchester Police/PA

The raid was part of Challenger, the largest ever multi-agency operation to target organised crime in Manchester.

Detective Inspector Chris Mossop, of Challenger's organised crime co-ordination unit, said: "This is a really significant discovery for Greater Manchester police. If what we have seized is proven to be viable components capable of constructing a genuine firearm, then it demonstrates that organised crime groups are acquiring technology that can be bought on the high street to produce the next generation of weapons.

"In theory, the technology essentially allows offenders to produce their own guns in the privacy of their own home, which they can then supply to the criminal gangs who are causing such misery in our communities. Because they are also plastic and can avoid X-ray detection, it makes them easy to conceal and smuggle."

He added that more work was needed to understand the scale of the problem.

Suspected 3D gun component parts found in Manchester police raid. Photograph: Greater Manchester Police/PA

"I would strongly urge anyone who has information about the whereabouts of a gun in their community to call us."

There have been suggestions on some websites that the parts were not gun components but printer parts – a spool holder and a drive block. Police said they were still concerned about the finding because they suspected the parts may have other uses.

A police spokesperson said: "We are aware of this suggestion, and it would be easier if it was cut and dried as to what these items are. But when you take it as a whole, including the discovery of gunpowder, it is disturbing."

A man has been arrested on suspicion of making gunpowder and remains in custody for questioning.

The technology works by allowing anyone who has a 3D printer – which can be bought on the high street for about £1,200 – to download designs for guns or components. The printers squirt molten plastic to produce 3D shapes of whatever design has been downloaded. The model parts can then be converted to become a firearm capable of firing bullets.