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Russian TV has apparently been hacked to show anti-war messages, as the country sat down to watch the Victory Day parades.
Messages appearing in TV menu screens included: “You have blood on your hands”, according to screenshots obtained by Reuters.
Since the war in Ukraine started, laws have been tightened against reporting anything that Moscow says is fake news or anti-Russian misinformation.
Monday is Victory Day in Russia — its celebration of winning the Second World War — and the military parade in Moscow is broadcast across the country.
Photographs from Reuters showed Moscow satellite television menus, with every channel displaying anti-war slogans.
“You have the blood of thousands of Ukrainians and hundreds of dead children on your hands,” said one slogan.
“The TV and the authorities are lying. No to war.”
The slogans appeared just before the Victory Day parade on Red Square at which President Vladimir Putin compared the war in Ukraine to the Soviet battle to defeat Adolf Hitler in the Second World War.
It was not immediately clear how the slogans appeared. Interfax news agency said the slogans also appeared on cable television after they were hacked.
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A Russian news website also showed anti-war material that was deeply critical of Mr Putin, Reuters reported. It was not immediately clear how the negative articles appeared and they were gone quickly.
Russia's invasion of Ukraine has killed thousands of people and displaced millions more.
Mr Putin casts the conflict as an inevitable confrontation with the US, which he accuses of threatening Russia by meddling in its backyard and enlarging the Nato military alliance.
Nato and Ukraine deny they were a threat to Russia. Ukraine says it is fighting a Russian land grab.