So big and bold it could be seen by a satellite in space, the warning "children" was painted outside a drama theatre where hundreds of Ukrainians, young and old, had been sheltering from Russian shelling.
Today, that theatre in the city of Mariupol was eviscerated, hit with what a Ukrainian politician said was a devastating 1000-kilogram Russian bomb.
MP Dmytro Gurin accused the Russians of knowingly bombing the building while women and children were hiding inside, and said acts of "mass murder" were now being carried out by Russian forces in Mariupol.
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"They just knew that it was bomb shelter and dropped 1000 kilogram bomb on this dramatic theatre," Mr Gurion told Today.
"The building is destroyed."
Satellite imagery firm Maxar Technologies said images snapped from space on Monday showed the word "children" had been written in large white letters in Cyrillic, the alphabet used in Russia, outside the building.
There was no immediate word on deaths or injuries in what the Mariupol city council said was a deliberate and targeted airstrike.
Ukrainian officials said there was no way the theatre could have been mistaken for a military target by the Russian aircraft that dropped the bomb.
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US President Joe Biden today declared Russian President Vladimir Putin a "war criminal" in a strengthening shift of rhetoric from Washington.
Satellite images from Maxar Technologies have previously been used to track a massive 64km-long Russian army convoy which had been snaking towards the capital Kyiv.
Source: 9News