On Fri, 15 Sep 2017 08:19:08 +0000 (UTC), d wrote:

Looks like it could be an improvised device, or some builders chemicals that
overheated. Hopefully the latter but seems unlikely to me.

http://www.bbc.co.uk/news/uk-41278545

There are reports of folks leaving the station with burns on exposed
flesh. It sounds like a chemical reaction. We can but hope it's not
"the religion of piece" proselytizing.