Cramer says he's worried by 'blowups' in some smaller stocks during Thursday's sell-off

Jim Cramer
Scott Mlyn | CNBC

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Big losses in some of the most impactful stocks like Apple and Microsoft on Thursday fueled the worst sell-off for the S&P 500 since June, but CNBC's Jim Cramer said it was losses by some under-the-radar stocks that had him worried about the days ahead.

Cramer joined "Closing Bell" after the market closed and pointed to three stocks that lost more than 20% on Thursday that would make Wall Street nervous.