WASHINGTON — The House voted on Tuesday to extend a law banning firearms that can pass undetected through airport X-ray machines, but left out provisions that law enforcement officials say are necessary to combat the growing threat of guns made with 3-D printers.

The legislation was approved overwhelmingly on a voice vote, meaning House members on both sides of a politically fraught gun-safety issue avoided having their individual votes officially recorded.

The focus now shifts to the Senate, where Democrats will introduce a stricter measure of their own next week, along with the extension the House passed.

But they are expected to act on Monday, the day the law expires. That leaves little time for senators to debate the more controversial aspects of the legislation, which would impose new restrictions on 3-D printed weapons.