Onslow County is among nine areas on the East Coast that are certified as ready to respond in the event a tsunami strikes. Tsunamis are primarily considered a threat on the Pacific Coast. But emergency officials are paying closer attention to the potential for killer waves on the Atlantic Coast since the 2004 Indian Ocean tsunami that killed more than 200-thousand people in 11 countries. The government's West Coast and Alaska Tsunami Warning Center now watches out for the East Coast as well. A tsunami-detection buoy monitors for sudden changes in sea level 320 miles off Charleston, South Carolina. According to the National Geophysical Data Center, seven tsunamis have been recorded in Atlantic and Gulf Coast states since 1886.