The Senate approved a 10-year extension of a ban on plastic guns Monday, but chose not to adopt Sen. Chuck Schumer’s proposal to tighten rules on guns created with 3-D printers.

“Science fiction has become a reality,” the New York Democrat said of the evolving technology of 3-D printers, which can produce firearms that pose a “mortal danger to our safety.”

Schumer also cited a “dangerous loophole” in the bill that would allow individuals to remove metal parts from plastic guns to prevent detection.

“A weapon that fires a bullet can, in fact, not have any metal in it and therefore evade traditional detection devices,” said Sen. Bill Nelson, D-Fla., who supports Schumer’s proposal. “You can imagine the havoc that could be wrought on secure areas. … We’ve simply go to update the law with the technology.”

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