While lawmakers feud over the release of blueprints for 3-D-printed plastic guns, the Transportation Security Administration wants fliers to know that airport security screeners have been able to spot the so-called untraceable and undetectable weapons in carry-on bags. The 3-D-printed gun controversy erupted in June when Defense Distributed of Austin, Texas, reached a settlement with the federal government to allow it to make the plans for the guns available for download. Then a federal judge in Seattle issued a temporary restraining order to stop the release of blueprints, and a coalition of 20 attorney generals, including California Atty. Gen. Xavier Becerra, filed a motion on Aug. 2 to continue to block the release of the plans. But TSA officials say 3-D-printed guns and firearm components have been in circulation for years and have been found on passengers trying to board commercial flights. “TSA officers are trained and on the lookout for 3-D guns,” he said. “We have proven detection capabilities and screening protocols in place.” Like all firearms, explosives and replica weapons, 3-D-printed guns are prohibited in the cabin of commercial planes. Passengers caught trying to bring any weapons into a flight are turned over to local law enforcement for prosecution and could face civil penalties of up to $9,800 imposed by the TSA.