DAVOS, Switzerland -- Interrogation methods at the U.S. prison camp in Guantanamo Bay, Cuba, are still a concern, Sen. John McCain said Friday, calling on authorities to process the cases of prisoners held for as long as four years without charge. Some 500 men accused of links to Afghanistan's ousted Taliban regime or the al-Qaida terror network continue to be held at the prison camp. Only a handful of the prisoners have been charged. ''What I was concerned about and continue to be concerned about is interrogation methods,'' McCain said on the sidelines of the World Economic Forum. ''What is...