Updated 10:11 A.M. E.T.

LONDON (AP) — Police thought they’d made a major discovery, but they may have jumped the gun.

British officers said Friday they had seized what appeared to be gun components made on a 3-D printer — then, hours later, cast doubt on the find after technology experts said photos released by police appeared to be of parts for the printer itself.

The Greater Manchester Police force initially said officers found what appeared to be a plastic magazine and trigger, along with a 3-D printer, in a raid targeting criminal gangs.

The force said forensic specialists were examining the parts “to establish if they could construct a genuine device.”

Police said that if the gun were viable it would be the first such seizure in Britain.

After some observers pointed out that the images released by police resembled printer parts, the force toned down its language, saying detectives were attempting to “establish exactly what these parts can be used for and whether they pose any threat.”

“We need to be absolutely clear that at that this stage, we cannot categorically say we have recovered the component parts for a 3-D gun,” said Assistant Chief Constable Steve Heywood.

“What we have seized are items that need further forensic testing by national ballistics experts to establish whether they can be used in the construction of a genuine, viable firearm. “

A man was arrested for questioning and then released. He told Britain’s Press Association news agency that he owned the premises raided by police — a model shop — and used the 3-D printer to make plastic decorations and models. He said the suspected gun magazine was a spool holder and the “trigger” was another printer part.

Earlier this year a Texas company said it had successfully test-fired a handgun created with a 3-D printer, and posted blueprints for the weapon online. Such printers can be paired with a home computer to manufacture objects using layers of high-density plastic.

Authorities worry the technology could allow anyone to manufacture guns that would pass unnoticed through metal detectors.

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