Senior employees of Kommersant, a leading Russian publishing house, have been sacked after they published accusations of election fraud in parliamentary polls earlier this month by the party of Vladimir Putin, the country's prime minister.

It happened after Russia's president ordered an investigation into the allegations of vote rigging, which prompted tens of thousands to rally in Moscow and other cities on Saturday in the largest anti-government protest in the country's post-Soviet history.

Alisher Usmanov, the paper's oligarch owner, said a magazine editor and a senior manager were fired because of anti-Putin slogans published in this week's edition, which carried the front-page headlines: "How the elections were forged".

Even with the reported vote fraud, United Russia lost about 20 per cent of its seats in the parliament, retaining a narrow majority.

Neave Barker reports from Moscow.