Not that we are so pollyanna as to disbelieve such a thing were possible:
Western Intelligence services (CIA, MI6, MOSSAD) behind Recent Killing of 17 Russians. Russ is Being Severely Punished for Sharing Nuclear Technology with Iran and Selling Weapons to Syria.
But the quote attributed to Russia's North Caucasus envoy Aleksander Khloponin seemed quite extraordinary:
“We will find and punish the organizers of this terrorist act even if they are beyond our borders ; London , Washington or Tel-Aviv . We will not stay indifferent to what’s happening around us. That is why we should be alert and actively resist those who think they can rule our destinies, who do not want our children to have a normal future,”
But the URL cited at rian.ru has nothing of the sort. Checking the quote's provenance, however, we found what appears to be the original, sans "London , Washington or Tel-Aviv" at RT:
Moscow steps up security measures after deadly blast in North Ossetia.
“We should find and punish the organizers of this evil deed. We should not stay indifferent to what’s happening around us. That is why we should be alert and actively resist those who think they can rule our destinies, who do not want our children to have a normal future,”
For a Moscow envoy to make an accusation of Western intelligence operations in the Caucasus is not unimaginable, as there is some precedent...
Reuters: Russia's Chechen chief blames CIA for violence
But in this instance, as the quote insertion is easily discoverable, this could be another case of "Hacking the site and subtly changing the messages and data—merely a few words or phrases—may be sufficient to begin destroying the blogger’s credibility with the audience..." -as previously cited from the June 2006 JSOU report: Blogs and Military Information Strategy