[karajorma]

Nine prisoners have been killed in a botched prison break in the Democratic Republic of the Congo after one of them pulled the pin on a grenade but did not throw it, a police official said.

The incident on Sunday follows a rash of prison violence and escapes in the central African country, including the escape of nearly 1,000 detainees from a high-security jail in September.

"The civilian [prisoner] did not know how to use a grenade. He pulled the pin out but didn't throw it," the provincial chief of police, General Gaston Luzembo, told Reuters.

http://www.guardian.co.uk/world/2012/jan/01/congo-prisoners-killed-grenade-blunder

[StarSlayer]

'Old on to tha pin, throw the udder part!

[Dragon]

Hardly the first such incident. One Darwin Award went to a guy who thrown the pin instead of the grenade when trying to shake off pursuing police.
Tip: if you don't know what to do with a bomb, leave it alone. 

[Rodo]

Wait, that's important information!
Until now I actually believed that holding a grenade without the pin on was possible, that it didn't blow up until that lever-thing was released.
Scary **** missinformation is.

[NGTM-1R]

Wait, that's important information!
Until now I actually believed that holding a grenade without the pin on was possible, that it didn't blow up until that lever-thing was released.
Scary **** missinformation is.

Depends on the grenade.

[Dragon]

It's likely he didn't knew to hold the grenade's spoon either, or it was the kind that didn't had a spoon (though I doubt it, most hand grenades since WWII have them).
Or, he was attempting a "cook off" (holding the grenade with spoon released to make sure it isn't tossed back) and got distracted.

[Rodo]

Or, he was attempting a "cook off" (holding the grenade with spoon released to make sure it isn't tossed back) and got distracted.

Scratch that, I don't think it's possible to get distracted while holding an active grenade.

[BloodEagle]

Do these prisons normally stock grenades in their armory?   

Or did they, er, you know... sneak it in.  That couldn't have been comfortable.   

[Dragon]

Scratch that, I don't think it's possible to get distracted while holding an active grenade.

http://www.darwinawards.com/
Don't tell me what's possible, OK? 
Human behavior is even less predictable than quantum physics. At least in the latter case, you can calculate probability functions. No such luck with humans, as the above link illustrates.
Seriously, who could have even thought that something like this could happen?:
http://www.darwinawards.com/slush/200910/pending20091020-134139.html
If this is possible, then an untrained person being distracted while holding a grenade seems almost unsurprising.

[deathfun]

For one, cooking the grenade is an idiot thing to do in the first place. After all, could be a faulty grenade, and prematurely detonates in your hand. Always assume it's going to be your first sexual encounter
But yes, Darwin at it's finest. If you don't know how to use a grenade these days, well damn. You know it's an explosive device, generally speaking, you want to throw it away from you

[Nuke]

first learn some respect for the little explosive implement of war, then read the ****ing manual, then make sure you can hurl it out of self killing range. when you can do all that, then use it as a weapon. until then, paperweight!

Or did they, er, you know... sneak it in.  That couldn't have been comfortable.   

people say prison rape is like a power thing, but really its how new inmates train for smuggling operations and holstering weapons.

[Nemesis6]

I'm not surprised that this happened -- The town mentioned is in the Kivu region; a part of the eastern part of the Democratic Republic of Congo, where people generally seem to be insane because it borders Rwanda and hence is filled with former militias, newly-sprung ones, and so on. The militias are finding this region very profitable, specifically in regards to mines where they can employ locals, or just have them work as slaves; either is acceptable. The entire region is basically controlled by these crazies. I could go on about crime, kidnapping, etc, but this little fact really nutshells it well: In the DRC, 400,000 women are raped every year.

Basically -- Not a very nice place.

[Mika]

Well, I was scared ****less when I had to throw a grenade for the first time during the military service. They had put a convenient 300 meter distance between the throwing place and the ammunition place where you assembled the grenade. Walking that distance with a secured live grenade in hand was already, let's say, exciting. But nothing can beat the testimony of my squaddie who had his instructor saying something like this (and remember, in the army you do exactly what you are being told to do and nothing else):

"Release the safety pin"
* Instructor rolls up a cigarette *
* Instructor lights the cigaratte *
* Instructor inhales cigarette smoke deeply *
* Instructor exhales deeply *
"Throw"

If that isn't real life badassery, then I don't know what could possibly be. The instructor probably had nerves of steel and ice in his veins, given that this was a rookie holding a live, unsecured grenade. I think his hands took extraordinary care of keeping the spoon pressed against the hull, possibly very tightly. My squaddie said all this took place in maybe thirty seconds, but that was one of the longest thirty seconds in his life...

[deathfun]

Said person, should have done a sleight of hand moment where he put the pin back in and fumbled the grenade as he was lighting up
Let's see how much nerves of steel he's got when he's looking at a "live" grenade at the base of his feet

[Herra Tohtori]

There is no way to insert a Finnish regulation hand grenade safety pin with "sleight of hand". To remove it, you must first pop the pull-ring up from where it normally rests, then twist the pin so that a small retaining claw or hook built into it releases, then you can pull it off the hole that goes through the grenade's handle. After the pin comes off, you throw the thing as far as possible, the spring-loaded handle pops off typically while grenade is in the air. That triggers the time fuse, which then detonates the grenade.

To re-insert the pin you would need to retain the grip on the grenade (you do not want to accidentally let the handle pop up while you are still holding the grenade in your hands, so yeah, no real way to secretly (and healthily) re-insert the safety pin.

[Mika]

There is no way to insert a Finnish regulation hand grenade safety pin with "sleight of hand". To remove it, you must first pop the pull-ring up from where it normally rests, then twist the pin so that a small retaining claw or hook built into it releases, then you can pull it off the hole that goes through the grenade's handle. After the pin comes off, you throw the thing as far as possible, the spring-loaded handle pops off typically while grenade is in the air. That triggers the time fuse, which then detonates the grenade.

To re-insert the pin you would need to retain the grip on the grenade (you do not want to accidentally let the handle pop up while you are still holding the grenade in your hands, so yeah, no real way to secretly (and healthily) re-insert the safety pin.

And luckily it is this way. Make no mistake, it is a design decision: it doesn't go off accidentally, and you can't make it look like it would be safe when it isn't. Removing the pin is your consent to the BOOM. You may postpone it for some seconds, but there's no way around it. Besides, a pin inserted back to the grenade doesn't really inspire any sort of confidence towards the thing, at least for two reasons. Seeing that in a movie... well,  then it's usually unintentionally funny movie anyways.

[Herra Tohtori]

Although you can create clever traps by putting the grenade into a flush-fitting glass jar. Pop off the pin, handle stays put until the glass jar shatters. You can compound the effect by tying either the jar or grenade or both to a door. Undesireables enter building, open door, grenade jar drops on floor, spring-loaded handle separates from the grenade frame...

Entrapments like this were actually taught to us as a hypothetical option to trap buildings because FDF is ending the use of anti-personnel mines, but not the use of hand grenades...

[Nuke]

i dont see why they dont put impact triggers on these things. instead of triggering the fuse, spoon coming off (in flight) arms the accelerometer trigger, this is after the grenade is accelerated by the thrower, so the act of throwing it wont set it off. then as soon as the accelerometer measures an appropriate change in velocity, detonate the thing. this would eliminate throwback potential. of course if somone was untrained in its use, might allow the spoon to fall before throwing it, and have it go off when they toss it. not quite a good idea. i guess its just as effective to use a faster fuse and require that the spoon come off in flight. doesnt change the predicament at all. from a technology standpoint were talking $4 worth of electronics.

[BloodEagle]

What if you need to roll the grenade, or bounce it off of something?

[Dragon]

Also, some consider "cooking" a grenade to be actually useful, believe it or not. Accelerometer would also negate this, with lethal consequences if attempted (with normal grenades, some people did survive doing this).