The Spaniards slipped to defeat on penalties but had two goals controversially disallowed during the course of the match.
Ivan Helguera had an effort ruled out for an innocuous-looking foul, while an arguably worse judgement was the linesman`s decision to chalk off Fernando Morientes` extra-time header.
The Real Madrid man headed home Joaquin`s deft cross, but the celebrations were cut short by the linesman who claimed the ball had gone out of play.
Spain eventually slipped to defeat, 5-3 on penalties, after Joaquin saw his effort saved by Lee Woon-jae and Hong Myung-bo stepped up to stroke home the crucial fifth.
An irate Helguera had to be restrained after the game, while Camacho was also angry with the officials.
Camacho said: "I thought the referee would be fairer in a quarter final match like this.
"We fought to the end and worked so hard but we went out because South Korea were luckier than us. I am just sorry we couldn't go any further."
Camacho did, though, praise his defeated charges, saying: "All I can do is congratulate my players."
Casillas, who kept a clean sheet through 120 minutes but was beaten by five penalties, implied that Spain were the victims of bias.
He added: "We'd already seen this when South Korea played against the United States, Portugal and Italy.
"Penalties are a lottery. We won last week and today we lost.
"We've been sent home without losing a match.
"Now we must wait another four years for Germany 2006."
