European stock markets soared Wednesday, bouncing back from sustained heavy losses on hopes that European nations will back their banks to prevent the eurozone crisis from spreading. Germany led the way, with the Frankfurt DAX index up more than 5.0 percent, Paris gained more than 4.0 percent while London, Milan and Madrid all put on more than 3.0 percent as investors focussed on the banks and shrugged off a sharp Moody's ratings downgrade of Italy.