As noted in the comments on The Verge's article[1], these parts actually seem to be replacement MakerBot parts. This feels like nothing but 3D printer scaremongering.
http://www.theverge.com/2013/10/25/5027282/uk-police-seize-3...
http://www.theverge.com/2013/10/25/5027282/uk-police-seize-3...
Did you hear that they confiscated knitting needles from an old lady before she was allowed to board her flight? They were afraid she was going to make an afghan.