1.If irregularities or information give rise to a suspicion that a ship which is voluntarily within a port or at an off-shore terminal of a Member State has been engaged in or is engaging in a discharge of polluting substances into any of the areas referred to in Article 3(1), that Member State shall ensure that an appropriate inspection, taking into account the relevant guidelines adopted by the International Maritime Organisation (IMO), is undertaken in accordance with its national law.
2.In so far as the inspection referred to in paragraph 1 reveals facts that could indicate an infringement within the meaning of Article 4, the competent authorities of that Member State and of the flag State shall be informed.