CHICAGO — There were busted barricades, bruised bodies and backflips on Saturday at Lollapalooza, though only two of those things occurred during Rage Against the Machine's set.

(See all our photos from Saturday right here.)

The agit-rock icons capped off the festival's second day with an incendiary, pummeling display of power that proved that they're still at the top of their game — though it probably wasn't Zack de la Rocha's screeds or Tom Morello's fret-bending guitarwork that people were talking about after the set. Instead, it was the ugly turn the night took shortly after RATM began their set.

The reunited group opened with a trio of their bombastic best, including "Testify" and "Bulls on Parade," setting off multiple circle pits in the crowd and sending a stream of bodies — which appeared to be equally comprised of crowd-surfers and panicked fans trying to escape the crush — over the barricade in front of the stage. By the third song, there was a steady, at times frenzied, rush by hundreds of fanson the east side of the stage attempting to leave the area. The relentless fury of the music, combined with the sense of chaos in the crowd, made for some tense moments. Concertgoers trying to go up a set of cement steps were pushed backwards or blocked from exiting as a bull rush of male fans barreled down the steps, knocking people over like dominoes.

The crowd surge got so bad that De la Rocha stopped the show on three separate occasions, pleading with fans to take a step back to avoid crushing the audience members up front, then introducing fist-pumping songs such as "Bullet in the Head." At another point during the set, Lollapalooza's head of security conferred with the members of the band and their team at the front of the stage.

There was also at least one reported security breach of the venue's perimeter fence, according to both the Chicago Tribune and the Chicago Sun-Times, resulting in an unknown number of fans without tickets rushing into the park and reportedly injuring some security personnel in the process. Spokespeople for the festival could not be reached for comment at press time, and a Chicago Police Department spokesperson said that officials had not received calls for help from the festival, despite multiple reports that police on horseback had responded to the fence breach.

Chicago Fire Department spokesperson Larry Langford said that as of 12:30 a.m. Sunday (August 3) his department had not received any calls for assistance from the private firm handling emergency services for the festival; MTV News is attempting to reach that firm. It was unknown at press time how many injuries occurred during the show, but an MTV reporter near the front of the stage witnessed at least a dozen dazed, limping and panicked fans being escorted to the medical tent, including one who was taken out on a backboard.

(Check out our Friday Lollapalooza recap here.)

It was an ugly and unfortunate end to what had been an otherwise idyllic day in Grant Park. The weather cooperated (sunny and breezy, not nearly as brain-melting as had been advertised), and the musical moments shone bright. The Ting Tings bleeped and shimmied in the early afternoon sun, MGMT were their usual psychedelic selves, and Explosions in the Sky coaxed grandeur out of their guitar pedals. Tyke rockers the Tiny Masters of Today blasted away on the Kidzapalooza stage (even working a protest song, "Bushy," into their set), Sharon Jones and the Dap-Kings ground out an hour of pulse-quickening R&B, and Wilco jammed through a good-natured 90 minutes that took place at the same time all the Rage chaos was unfurling.

But the early part of Saturday belonged to Chicago's own Lupe Fiasco, who made a major statement on his third trip to Lollapalooza and emerged as a conquering hero, stepping way outside the shadow of mentor Kanye West, who closes Lolla on Sunday night. And he did it from the get-go.

Taking the stage to the theme from "Rocky" — performed by a fabulously funky nine-piece backing band that included bass, guitar, drums, DJ, three horns, backup singer, hype man and keyboard player - Lupe bobbed and weaved like a prize fighter but dressed like a futuristic Space Gentleman (in impeccable white and silver, down to his shining high-tops). He dropped to the floor to rip through some one-armed push-ups, sprang back to his feet, threw himself into an impressive backflip and welcomed the huge crowd to "Lupepalooza."

And he didn't let up from there. The band turned the normally lazy tempo of "Kick, Push" into an old '70s funk jam as Fiasco ran from one end of the stage to the other, stalking it with a super-sized confidence that surpassed the swagger he displayed at Lolla last year.

The ensemble was later augmented by a children's gospel choir, and during "Hip Hop Saved My Life," Fiasco copped a sly smile as he waved his hand in the air and thousands of converts followed suit. This was a man becoming, well, the man.

It was epic, it was grandiose, and it was all anyone could talk about ... until Rage, of course. Your move, Kanye.