HE never saw it coming, and neither did anyone watching “The Wire” last night on HBO.

Omar Little, the scar-faced stick-up king who fearlessly stole money and drugs from Baltimore’s toughest gangs and then outfoxed them in their efforts to exact retribution, was shot to death last night while buying a pack of cigarettes.

His murder came as a shock because Little – as played by Michael Kenneth Williams – was so tough that he seemed invulnerable. No one dared step to him; in fact, his reputation was so fearsome that residents of the neighborhoods in which he operated would scatter and run for cover when they heard he was coming.

Even more surprising: His killer was a boy not more than 11 years old – Kenard (last name unknown), a potty-mouthed, entry-level corner boy working for drug kingpin dealer Marlo Stanfield. At the time of his death, Omar happened to be hunting for Stanfield.

Kenard (Thuliso Dingwall) spotted Omar entering a con venience store and ap parently followed him inside. Just after Omar asked a Korean storekeeper for a soft pack of Newports, Kenard shot Omar through the head.

The deed brought an end to a character who, despite his stone-cold criminality (or perhaps because of it), was one of the most popular characters on “The Wire.”

His death – so unimaginable in previous seasons – is also a sign that “The Wire” is almost over. Just two more episodes remain, including the series finale on March 9.