Earlier reports suggested at least 51 people, including 20 children, had been confirmed dead, but it now appears some victims had been counted twice.
Teams are continuing to search the rubble. More than 140 people are being treated at hospitals, including about 70 children, and some were in critical condition.
At Plaza Towers Elementary School, the storm tore off the roof, knocked down walls and turned the playground into a mass of twisted plastic and metal. Several children were pulled alive from the rubble.
“I saw some… people, for the last time, alive, at the centre, trying to get away from the hail,” said a lucky survivor.
US President Barack Obama has called Oklahoma Gov. Mary Fallin to express his concern.
The White House says Obama told the governor that he’s directed the government and the Federal Emergency Management Agency to provide any assistance she needs. FEMA has sent a special team to Oklahoma’s emergency operations centre to help out and dispatch resources.
The White House says Obama’s homeland security team is keeping him updated on the situation.
The more than 1.6 kilometre wide, EF-4 tornado flattened entire neighbourhoods in the southern suburb of Moore with winds up to 320 kph.