French Interior Minister Bruno Retailleau and British Home Secretary Yvette Cooper pledged to step up the fight against illegal Channel crossings during a visit to the coastline of northern France from where tens of thousands of people leave every year to make their way clandestinely to Great Britain. Illegal border crossings have long been a sticking point in ties between Britain and France. Faced with tighter security, both smugglers and undocumented migrants are now taking greater risks, experts say. COMPLETES VIDI36YQ4VN_EN IMAGES AND SOUNDBITES