Oh wow, does this article ever try to drown readers with suggestive trigger terms: 'likely Russians,' presumed Russian'...
Just repeating the same suggestive term over and over and over... 
People, this article is an instance of an influence operation, and is how brain-washing is done through propaganda.
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"the presumed Russian spending..."
There was a recent G&M article asking whether readers' English skills were as good as a G&M journalist. Shouldn't that be 'the presumed-Russian spending'? Also, that's a determination in search of evidence.
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"A Facebook employee said Wednesday that there were unspecified connections between the divisive issue ads and a well-known Russian "troll factory" in St. Petersburg"
You mean an alleged Russian "troll factory." The most evidence we've seen to back that up was a photograph taken from across the street with ominous words to go along with it. Very much like Colin Powell holding up a vial of white powder and telling Congress that Iraq has WMDs.