UPDATE: February 9, 2015, 12:00 PM EDT
Dr Douglas McGregor, a researcher in Nuclear Physics at the University of Glasgow, told the Huffington Post: “To my mind the videos show a large explosion, which is most likely to be a very large conventional explosion.
“However, from the pictures I could not categorically rule out a small nuclear explosion. The acid test will be to monitor to see if there is any radioactivity in the vicinity when observers gain access to the site.”
The blast was heard for miles and shattered windows across Donetsk.