Sorry but I have NEVER heard of a flashlight exploding because of old batteries (unless you throw it in a fire).
So a small explosion closing an airport? NOT an over reaction at all.
You do realize that most explosives have a primer and a main charge, and an explosion of a primer (that failed to detonate a main charge) would be smaller than the description of this explosion . Infact the way explosives are smuggled on is to try and seperate the battery, primer and main charge so it wouldn't look like a bomb to an xray machine.
This is on that is VERY difficult to question by anyone with any knowledge of explosives and security. I suspect this is just another round of America bashing. Have your fun.
Cheers
Wino