[joshmaker]

I think a lot of people would think the fact that a nuclear power plant core had exploded was evidence enough that an evacuation was needed.

[egao1980]

At first there were no signs of contamination outside of the station and it was unclear if reactor has exploded or not. Evacuation started as soon as that fact was established.

In one of the US nuclear incidents people died while evacuating in panic though no one got hurt at the power plant .