Since the outbreak of COVID-19, there's been a global race to find a vaccine.
But scientists are worried some countries may be rushing the process and compromising safety.
Earlier this week, Russian president Vladimir Putin said his country has approved the world's first coronavirus vaccine.
But Scientists in Russia and abroad are sceptical about its effectiveness.
They say offering it to the public before the important final stage of testing, could pose serious problems.
So, were Russian scientists pressured to cut corners?
And is there significance to the timing of the announcement?

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