against terrorists. >> reporter: the waters twoen here and northern france and the british coast are trechouserous, busy, and this time of the year very cold. we've had near misses before. a bad accident was predictable. but this loss of life is clearly terrible. now, a criminal investigation has started. a number of suspected people smugglers have been arrested. the question is how will this disaster change the debate about how france and the uk should manage cross channel migration? britain has long claimed the french should do more to stop these boats leaving. last month we filmed these people running down a beach near calle with their boat headed for the uk and watched by the french police who did not intervene. but now political debate has coincided with tragedy. one of the first people to reach the scene in the middle of the channel was this life boatman.