The media succumbed to confirmation bias in response to a UN report on the attack. That report, which is less than certain in its terms, said that the spent weapon "indicatively matches" the specifics of a 330mm calibre artillery rocket. MIT professor Theodore Postol and other munitions experts later reviewed the photos and said that it was improvised, likely made locally, didn't match anything in the Syrian arsenal and would not have been able to travel the nine kilometres from the Syrian army base that the media presumed it was fired from.
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