PARIS, July 23 (Reuters) - French authorities said on Friday they had rescued a boatload of 42 migrants in the English channel after their boat got into difficulty. The emergency services were alerted by the migrants, and a rescue vessel picked them up in the sea off the Pas-de-Calais area, according to a French police statement. They were taken to the nearby port of Boulogne-sur-Mer, and all are in good health, the statement said. Thousands of migrants each year attempt the dangerous sea crossing from France to the coast of Britain, often paying human smugglers to help them through one of the world"s busiest shipping lanes in overloaded rubber dinghies. Britain has repeatedly pressed French President Emmanuel Macron"s government to do more to prevent the migrants leaving France.