“The San Remo Manual on International Law Applicable to Armed Conflicts at Sea was adopted in June 1994 after a series of round tables of naval and legal experts convened by the International Institute of Humanitarian Law. In paragraph 67 it permits belligerents to attack merchant vessels flying the flag of neutral States if they “are believed on reasonable grounds to be carrying contraband or breaching a blockade, and after prior warning they intentionally and clearly refuse to stop, or intentionally and clearly resist visit, search or capture”. Paragraph 146 permits the capture of neutral merchant vessels outside neutral waters if they are engaged in any of the activities referred to in paragraph 67.”