evidence: A video purporting to show intense fighting between Russian and Ukrainian forces outside a block of flats has racked up 7.7 million views. [...] A video of a column of Ukrainian tanks in central Kyiv was presented as if they were on their way to defend the capital against a Russian offensive. It received nine million views. But it was filmed during an independence-day military parade several years ago. And a video of a tank with a Ukrainian flag, speeding down a residential street - viewed four million times - also dated back to the Russia-Ukraine conflict of 2014.