LOS ANGELES (CBSLA.com) — Rolling Stones fans who didn’t check their Twitter accounts Saturday morning missed out on a once-in-a-lifetime opportunity.

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The legendary and seemingly tireless rock band announced Saturday morning that they were going to throw an impromptu concert that night at the Echoplex  in Echo Park.

Fans coming out of the venue told CBS2’s Brittney Hopper “they were amazed.”

One fan exclaimed, “It’s a small venue. I’m going to be able to see Mick’s [Jagger] lips up close.”

And Wayne Johnson said he’s seen the Stones, “half a dozen times, and as far back as 40 years ago, but never in a small place. It’s going to be a whole different atmosphere.”

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The venue seats only 650 and for five decades the Stones have been selling out stadiums and huge arenas.

Tickets went on sale at noon — $20 cash only — and no surprise, sold out by 2 pm.

The band said they were using the surprise show as a warm-up gig for their “50 & Counting Tour” which kicks off at the STAPLES Center on Friday, May 3.

The set list from Saturday’s show (14 songs in all) included “Start Me Up,” “Brown Sugar,” “Jumpin Jack Flash” and “She’s So Cold.”

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