WASHINGTON (AP) – President Bush quietly signed legislation Tuesday that would extend for 10 years a ban on plastic guns that can be slipped past airport metal detectors or through X-ray machines.

The legislation bans the manufacture, sale or possession of such firearms, but exempts military and intelligence agencies. It renews a ban that was last reauthorized in 1998 and expires this month.

It was passed as officials worry that terrorists would get their hands on weapons undetectable by metal detectors at airports and other security checkpoints.