Gov. Kate Brown again called for a moratorium on oil trains in Oregon, after federal regulators released findings June 23 that blamed this month's fiery derailment and spill in the Columbia River Gorge on Union Pacific's failure to maintain its tracks.

Oregon has asked the Federal Railroad Administration to place an open-ended moratorium on oil trains traveling through the state, because preliminary findings of an investigation into the June 3 derailment in Mosier suggest inspectors might not be able to detect the problem that likely caused the crash.