The Kremlin accused the Wall Street Journal of publishing "pulp fiction" on Friday after it reported that the death of mercenary boss Yevgeny Prigozhin in a plane crash had been orchestrated by Russian security official Nikolai Patrushev.
The WSJ reported that Prigozhin's private jet was downed by a small bomb placed under a wing. Its report cited unnamed Western intelligence officials and a former Russian intelligence officer.
Kremlin spokesman Dmitry Peskov said he had seen the story but would not comment on it, before adding: "Lately, unfortunately, the Wall Street Journal has been very fond of producing pulp fiction."
Prigozhin, head of the Wagner mercenary group that fought for Russia in Ukraine, waged a long-running feud with the defence establishment that culminated in an outright mutiny in late June. It ended quickly but was widely seen as a serious challenge to president Vladimir Putin's almost quarter-century-old grip on power.
Prigozhin died in a plane crash exactly two months later. The Kremlin has previously rejected as an "absolute lie" the suggestion that he was killed on Putin's orders. Putin suggested in October that the crash was caused by hand grenades detonating inside the aircraft.
Nine other people were also killed: two other top Wagner figures, Prigozhin's four bodyguards and a crew of three.
Patrushev, 72, is a former head of the FSB security service who now serves as secretary of Russia's Security Council and is considered one of the most influential hardliners among Putin's close advisers.
The two have known each other since working together in the Soviet KGB in Leningrad - now St Petersburg - as far back as the 1970s.
