0893 - In Ardabil, Iran, an earthquake killed about 150,000 people.
1913 - In eastern Nebraska and western Iowa 181 people were killed by 8 tornadoes.
2005 - In Texas City, TX, 15 people were killed and more than 100 were injured in an explosion at a gas plant.
2010 - The South Korean Navy ship ROKS Cheonan sank off the country's west coast. Forty-six of the 104 personnel were killed. An independent investigation blamed North Korea for the sinking. North Korea denied the allegations.
Tomorrow in Disaster History.