The Daily Mail, a publication in the UK, recently built a 3D printable gun and smuggled the firearm on to a packed Eurostar train.
The Daily Mail found the plans for the 3D gun on the web and printed the parts needed for the firearm.
Two Daily Mail reporters made it through security and carried the 3D gun on a London to Paris trip, with hundreds of unsuspecting travelers on board.
"Because all the parts are plastic, they did not trigger the metal detectors all Euro-star passengers must pass through," reported the Daily Mail.
Once aboard the train, the Daily Mail reporters put together the gun pieces in 30 seconds, and posed for pictures close to passengers.
However, the Daily Mail admitted that the reporters did not try to smuggle the necessary firing pin or a bullet, which are metal and likely could have been discovered by security.
The blueprints for the unusual gun were downloaded more than 100,000 times last week from "Defense Distributed" founder Cody Wilson, who posted his blueprints for the 3D printable “Liberator” handgun online.
The U.S. government ordered Wilson to take them off the web, but the blueprints are still available on torrent sites such as The Pirate Bay, reported TorrentFreak.com.
"Eurostar has a high level of security, with a number of checks as specified by the authorities in order to protect the integrity of the Channel Tunnel. We take any issue relating to security very seriously," a Eurostar spokeswoman stated on Sunday.
"We will be investigating immediately to fully understand the nature of this issue with our security partner which carries out checks on our behalf at St. Pancras. We will also investigate the matter with the Department for Transport, who oversee our security operation, and specify the checks that need to be undertaken."