'We've got some hope' for those trapped underground, says engineer

The ferocity of Wednesday's flash floods has erased almost every record of power stations in many locations in northern Nepal, according to engineer Professor Arnold Dix. Dix, who is advising on the rescue efforts from Melbourne, says locating these power stations, where hundreds of workers are said to be trapped in tunnels, was one of the first challenges rescuers faced. Speaking to Radio 4's World at One, he says he has been using satellite data to compare with ground photos and information fr