During the searches, officers found a Makerbot Replicator2 3D printer and two 3D printed component parts thought to be a magazine clip and a trigger. In addition, a man was arrested on suspicion of making gunpowder and remains in custody for questioning.

The parts are being examined by firearms specialists to establish whether they could be used to construct a working firearm; if they are found to be viable components for a 3D printed gun, it would mark the first seizure of its kind in the UK.

Detective inspector Chris Mossop of Challenger's Organised Crime Coordination Unit stressed the significance of the discovery and the threat posed by criminal gangs using 3D printers, which can be bought on the high street for as little as £1,200, to manufacture weapons.

"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," he said.

"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 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."

Currently the Home Office seems less concerned with the ease with which criminal gangs can access 3D print technology - a Home Office spokeswoman said: "We’ve made it clear that, including 3D printing, if you don’t have a licence [to produce firearms] you’re going to be prosecuted – it’s up to the police to make sure that our laws are being enforced."

Asked whether the government was looking at ways to tackle the risk of 3D printed weapons, such as by controlling the sale of the printers or requiring distributors of the devices to keep a register of customers, she said: "We’re always obviously continuing to monitor the use of 3D printing capability for that purpose [but] I’m not sure how far we’d go into that at the moment."

The raids were carried out as part of Operation Challenger, the largest ever multi-agency attempt to target organised crime in the history of GMP, in the Baguley area on Thursday 24 October.