UPDATE 9:51 pm: Officials in Joplin, Missouri now report at least 122 people have been confirmed dead as a result of the tornado.
In Joplin, Missouri, at least 117 people were killed by an F4 tornado and more than 1,000 are unaccounted for, according to the New York Times.
It's the worst tornado to hit the United States in 64 years (181 people were killed by a tornado in Woodward, Oklahoma in 1947), and it surpasses the death toll of Michigan's worst tornado which struck in 1953.
The 1953 Flint-Beecher Tornado killed 116 people in a community just north of Flint. The F5 tornado is listed as the country's 10th deadliest tornado by NOAA's Storm Prediction Center.
The tornado had winds in excess of 200 miles per hour, was 800 yards wide, and traveled on a path for 27 miles. From NOAA:
So great a number were killed by the monstrous tornado that the National Guard Armory building, along with other shelters, was turned into a temporary morgue. The scene of bodies pouring into the Armory (as an intermittent light rain poured outside) was incredibly bleak and horrifying, especially for the families and friends of the victims. At least 100 people waited outside into the rainy night before they could move inside to try and identify the bodies.