They want Gibraltar to become part of Spain, not the other way around;
The Interior Ministry on Wednesday ordered the Civil Guard on the frontier with Gibraltar to prevent trucks laden with Spanish sand from entering the British outpost. The sand, which is being taken from the dunes at Valdevaqueros in Tarifa, is then used in land reclamation for a property development and the regeneration of the Sandy Bay beach on the Rock.
The prohibition was put into action after consultation between the Interior Ministry, Customs and Excise and the environmental arm of the Public Prosecutor’s Office. It follows a complaint lodged by ecologists on July 17 against the municipal government of Tarifa, over which a judicial process has been initiated. The potential charges that could be leveled include “aggravated robbery” and falsification of documents.They'll always have the Sahara.