Radiation from the Fukushima leak has been detected across Britain, it was confirmed today as Japan was put on 'maximum' alert. The Health Protection Agency revealed that radioactive iodine had already been discovered 5,500 miles from the stricken plant in Oxfordshire and Glasgow. The news comes as it was reported that the radioactive core of the stricken reactor has melted through the bottom of its containment vessel, onto a concrete floor, raising fears of a full scale meltdown. Air samples are being tested elsewhere in Britain over fears that much of the country could be hit by the radioactive plume. Dr Michael Clark of the HPA said: 'Very low levels of radioactivity, traceable to Fukushima, have been detected at monitoring stations in the UK including Chilton, in Oxfordshire, and Glasgow, in Scotland. (Daily Mail)