Yup, must have been Russia. At the worst possible political time, especially with the upcoming World Cup, they must certainly have murdered, in the most blatant way possible, a former spy because, well just because. They don't need a motive.
No point waiting for an actual investigation to be conducted, the substance to be analysed and identified, or even for any actual evidence to be presented. Russia must prove that it didn't do it within a tight timeframe provided by the UK foreign office, and without having any access to the crime scene, otherwise they will be punished.
It's like the UK has so little confidence in their team for the World Cup, they are just looking for (MI6) to create any excuse to have them not compete.
And now that you're all distracted from UK arms sales to the Saudi's to slaughter the Yemeni's...
RE: US Blames Russia for Chemical Attack in UK as Haley Warns UN of Russian Chemical Weapons in NYC