From the BBC and finally the 2017 Buzzfeed reports gain traction:
During the urgent question in the Commons, Labour's Yvette Cooper raised reports by BuzzFeed that 14 deaths in the UK had been linked to Russia by US spy agencies.
Ms Cooper, chairwoman of the Home Affairs select committee, asked Mr Johnson and the home secretary to order the National Crime Agency to urgently review the cases.
Mr Johnson said there were "a number of deeply troubling cases" and he would "certainly have that discussion with the home secretary".
Link:http://www.bbc.co.uk/news/uk-43312625