[pabianice]

Is this like the nuclear hand grenades Idi Amin accused Israel of using during its raid to free hostages in Uganda?

[xm177e2]

Amin probably just wanted a few of those grenades for himself, so he could microwave his meals while he was out and about...

[JIMJFOX]

Very doubtful.AFAIK, the minimum mass of plutonium/enriched uranium for fission to occur is at least 5kg; add to this conventional explosives and the containment, a hand grenade would weigh far too much to be practical.
Smallest nukes I know of would be 155mm artillery shells, which have been abandoned as too expensive.