UPDATED: 2/28/2013 3:30 p.m.

CHICAGO (CBS) — The CEO of Chicago-based Groupon is out of a job, while the company’s stock plummeted on Thursday, falling about 25 percent.

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Groupon closed at $4.53, as investors continued to express concerns about weak earnings reports.

After the close the company announced the ouster of CEO Andrew Mason. Executive Chairman Eric Lefkofsky and Vice Chairman Ted Leonsis will take over Mason’s role.

“After four and a half intense and wonderful years as CEO of Groupon, I’ve decided that I’d like to spend more time with my family,” Mason said in a memo to Groupon staff.”Just kidding – I was fired today. If you’re wondering why–you haven’t been paying attention.”

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The stock immediately jumped about 8 percent a share in after-hours trading following the news.

The online daily deal site has been suffering since its initial public offering in November, 2011. Also Thursday, several analysts downgraded the stock.

The plunge comes after Groupon closed Wednesday at a six-month high of $5.98.

A year ago, Groupon stock was trading near $20, before plunging to less than $3 a share in October, 2012.

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