Oklahoma Tornado is One of the Worst Global Tornadoes with 300 Plus Deaths

A 40-minute, mile-wide tornado that swooped down the Oklahoma City suburb of Moore on Monday afternoon has killed 51 people. Almost half of the fatalities were children. Officials expect the death toll to rise.

With wind strength of 321 kilometres per hour, the violent twister flattened everything it came across with, including homes, building structures, cars, trees and shrubs.

Oklahoma has been immediately declared a major disaster area by President Barack Obama, ordering the immediate release of federal aid and logistics to supplement state and local rescue and relief operations.

The twister descended on Moore, a town of 50,000, at 3:01 p.m. local time, just when the children were about to leave school for their homes. At least two dozen school children are still being searched under the rubble of Plaza Towers Elementary School, which took a direct hit from the tornado.

This is the second time that Moore got hit by a devastating tornado, the first in in 1999, which killed 46.

Monday afternoon's tornado, according to the National Weather Service, was an EF-4 on the enhanced Fujita scale, the second most-powerful type of twister.

Currently being treated at the hospitals were 120 people, 70 of which are children.

Authorities have not released total cost on damages to property.

People are hoping the death toll in Moore won't be so many to reach a hundred, like those recorded in the world's worst tornado disasters.

The deadliest tornadoes by far have occurred in a small area of Bangladesh and East India.

List of tornadoes with 300 plus deaths:

1) Bangladesh, April 1989, 1,300 dead

2) East Pakistan (now Bangladesh), April 1969, 923 dead

3) United States, March 1925, 695 dead

4) Bangladesh, April 1973, 681 dead

5) Malta, September 1551, 600 dead

6) Bangladesh, April 1964, 500 dead

7) Italy, December 1851, 500 dead