Thirty five years ago today a nuclear reactor in Europe suffered a series of catastrophic explosions.
Copious amounts of radioactive material were thrown into the air and carried great distances as a fire burned uncontrollably.
The explosions had blown off the heavy steel and concrete lid of the reactor, allowing it to spew several times more radioactive material than that created by the atomic bombs of Hiroshima and Nagasaki.
Firefighters attempted to put out the wall of flames, but it was too late.
Two people had already lost their lives, another 28 would die within the next three months, and thousands more would suffer the long-term health consequences of intense radiation exposure.
The disaster took place near the city of Chernobyl – a name that has since become synonymous with nuclear disaster – in what was then known as the USSR.
Despite the towering flames and clouds of toxic smoke, no one from the surrounding town of Pripyat was evacuated until about 36 hours after the first explosion, as the secretive Soviet Union embarked on a major coverup.
At first, they denied an accident had taken place.
But the explosions were so catastrophic that radioactive material soon made its way to Sweden, where officials at another nuclear plant began to ask questions about what was happening in the USSR.
Their inquiries meant the Soviet Union had no choice but to issue a short statement on April 28 confirming an incident had occurred.
It was the beginning of the end for the troubled regime.
The failed cover-up exposed the hypocrisy of Soviet leader Mikhail Gorbachev, who earlier that year had committed to increasing openness to the West under the political slogan of Glasnost.
In a 2006 interview, Mr Gorbachev said: “The nuclear meltdown at Chernobyl 20 years ago this month, even more than my launch of Perestroika (economic reforms), was perhaps the real cause of the collapse of the Soviet Union five years later.”