In the United States, at least 91 people have been left dead after a huge tornado tore through Oklahoma City suburbs. Officials said 20 children are among those killed in the devastation.

Worst hit was Moore, south of the city, where neighbourhoods were flattened and schools destroyed by winds of up to 320 kilometre per hour. About 120 people are being treated in hospitals.

President Barack Obama has declared a major disaster in Oklahoma. Hours after the storm struck, frantic search-and-rescue operation is still going on. Heavy machinery is being used under floodlights to try and find and free those still trapped under the tons of debris.