Border surveillance
Article 13
1. The main purpose of border surveillance shall be to prevent unauthorised border crossings, to counter cross-border criminality and to take measures against persons who have crossed the border illegally. A person who has crossed a border illegally and who has no right to stay on the territory of the Member State concerned shall be apprehended and made subject to procedures respecting Directive 2008/115/EC. 2. The border guards shall use stationary or mobile units to carry out border surveillance. That surveillance shall be carried out in such a way as to prevent and discourage persons from circumventing the checks at border crossing points. 3. Surveillance between border crossing points shall be carried out by border guards whose numbers and methods shall be adapted to existing or foreseen risks and threats. It shall involve frequent and sudden changes to surveillance periods, so that unauthorised border crossings are always at risk of being detected. 4. Surveillance shall be carried out by stationary or mobile units which perform their duties by patrolling or stationing themselves at places known or perceived to be sensitive, the aim of such surveillance being to apprehend individuals crossing the border illegally. Surveillance may also be carried out by technical means, including electronic means. 5. The Commission shall be empowered to adopt delegated acts in accordance with Article 37 concerning additional measures governing surveillance.