Cleveland Volcano in Alaska continues to be undergoing a low-level eruption following the Saturday's morning explosion, the Alaska Volcano Observatory and the United States Geological Survey said. Scientists said images captured by satellites and installed cameras were showing continuous low-level emissions of gas, mist and ash. A soft cloud of ash has extended eastward below 15,000 feet, and estimates have suggested that the clouds of ash could exceed even 20,000 feet above the sea level. Frenchtribune reports Scientists said in a statement, "Sudden explosions of blocks and ash are possible with little or no warning. Ash clouds, if produced, could exceed 20,000 feet above sea level." The level of aviation alert has already been raised to "Orange," from "yellow." A bigger ash emission could even threaten international flights. But, the Federal Aviation Administration has so far announced no flight restrictions. The eruption activity started with an exp