Second man arrested over London train attack - police

A second man has been arrested over Friday's bomb attack on a London underground train that injured 30 people, police said.The 21-year-old man was arrested in the west London suburb of Hounslow just before midnight on Saturday, the Metropolitan Police force said in a statement.Earlier on Saturday, British police arrested an 18-year-old man in the port of Dover and raided a property in Sunbury, a small town outside London, as they hunted for whoever planted the device.