LONDON (Reuters) – White brightly burning munitions were shown cascading down on the Azovstal steel works in the Ukrainian port city of Mariupol in what a British military expert said looked like either an attack with phosphorus or incendiary weapons. Reuters was not able to immediately identify the type of munitions being used or when the video was taken. It was posted on Sunday on the Telegram messaging application by Alexander Khodakovsky, a commander of the pro-Russian self-proclaimed republic of Donetsk. “If you didn’t know what it is and for what purpose – you could say that it’s even be…