Zabuza or Gaara?

I was re-watching the earlier episodes of Naruto earlier and got to the part where Kakashi first encounters Zabuza. Kakashi explains to Naruto about the Chuunin exam for the Hidden Mist village, about how the Genins are pitted against each other in fights to the death. It then showed a shot of a child surrounded by bodies and *something*.

Kakashi: The rules of the exam had to change when a child, who was not even a ninja, killed over 100 of the Hidden Mist Genin.

Zabuza: Ah yes. That was fun.

Now when I watched this the first time I assumed the child was a young Zabuza, but of course back then Gaara wasn't a known character. Now having watched it again the child looks a lot more like Gaara than Zabuza, and the *something* could be either sand or mist. Now I can't figure out which it was supposed to be:

Argument for Zabuza: He was a Hidden Mist Genin in the exam in a fight to the death. Why would Gaara go to the Hidden Village of Mist's Genin exam when he's from the Village of Sand? And why would he spare Zabuza if he killed the other Genins? He admitted it was fun, indicating he must've played some part in the killings.

Argument for Gaara: It looks like Gaara, and Gaara is younger than Zabuza so he wouldn't have been a ninja at that point, plus we're shown that Gaara kills skillessly from a young age because of the sand being sentient and under his control. Zabuza didn't have to kill 100, only 1. Also, he would've been classified as a ninja if he was a Genin.

1) Gaara has no reason to be there
2) Zabuza does
3) Sand ≠ mist
4) Chronography conflicts
5) Who cares what he looks like? The fact is that it WAS Zabuza.

There's no real argument here, only fact.

Well it's stated in latter episodes that Gaara did some high-level (A) missions at that age, maybe one of the missions was to kill all the Chuunins of the Mist so they wouldn't grow up to be powerful and cause problems for the Sand village later.

And why would Zabuza be in the Genin exam if he wasn't a Genin ("not even a ninja")?

Dude I'm sorry but is this a joke?

Naruto is not a complex show. That story was the background to Zabuza, period. That arc was about Haku and Zabuza. Zabuza was the one who killed the kids because why would he go "Oh yes, that was a good time" if all he did was watch Gaara kill everybody? The reason he's called "The Devil of the Hidden Mist" is because he's a former Hidden Mist Ninja who did some CRAZY sheisse during their trial that made them stop. You think Gaara did it and he took all the credit? Dude, it's just not that complicated. They were talking about him, about his past, and he's the one who did it.

"Still playing ninja? When I was about your age, these hands were already died red with blood."
"Zabuza... the Devil..."
"So you've heard a little about it."
"Long ago, in the Hidden Mist Village, often called the Blood Mist Village, there was a final obstacle to becoming a ninja."
"You even know about that graduation exam."
...
"Fights to the death between students..."
"Ten years ago...the Hidden Mist Graduation exam was forced to change......due to a great evil." *CLEAR PICTURE OF THE BACK OF YOUNG ZABUZA IN NINJA GEAR THAT GAARA DOESN'T/NEVER WEARS*
"What was this evil?"
"Without pause or hesitation, a young boy who was not even a ninja, had killed over a hundred of that year's students."
*cut to Zabuza looking REALLY evil*
"That sure was fun."

The stuff around the kid in the picture is clearly DUST. Because one hundred people had been fighting to the death. Zabuza and Gaara have similarly frizzly hair but that's it. Not to mention Gaara would've had to have been 2-3 years old, and let's be real, he was NOT doing missions at that age. Just think about it guys. They're not trying to throw you for a loop here. He wasn't a ninja yet because this was the *graduation exam*. Those who went on could become genins. They mention that he wasn't a ninja because it's that much more amazing that he killed a hundred people; you'd think someone not even out of ninja academy wouldn't be able to take on everyone like that. But he did, that's why he became famous.

Maybe Zabuza was a chunin or a jounin ninja at that point and was watching the fight as kazekages son-Lord Gaara tried his power or..was making sure of his existence against hidden village Mist's genins?


But then again gaara is like what..13-14 years old and he would be 3-4 so thats impossible...chibi zabuza just looks like him