Of the 91 people confirmed to have been killed by the Moore, Oklahoma tornado, seven were killed at Plaza Towers Elementary School. The school was almost directly in the path of the eye of the tornado. The image below shows the scale of the devastation.
US President Barack Obama declared a "major disaster" as rescuers combed through smashed homes and the collapsed remains of an elementary school in Moore, where twister-seasoned residents were shocked by the devastation.
The dead included at least 20 children, most of them under the age of 12, Amy Elliott, of the state medical examiner's office, told AFP.
Reporters for local broadcaster KFOR-TV saw children as young as nine being pulled out of the Plaza Towers Elementary School in Moore, a residential community of 55,000 just south of Oklahoma's state capital.
Anxious parents were being kept at a distance while search-and-rescue workers scrambled to free the students.
A second elementary school, Briarwood, was also hit but did not appear to have suffered casualties.