NEW YORK (CNN/Money) - General Motors, struggling with declining sales and profits, said Monday it is reducing its white-collar work force to lower costs.

The automaker's chief executive officer, Rick Wagoner, also purchased 50,000 shares of the company's stock, which tumbled to a 12-1/2-year low after its warning last week of weaker-than-expected profits.

GM (Research) shares, which last week fell about $5.30 or more than 15 percent, bounced back about 4 percent on Monday to close up $1.07 at $29.69 on the New York Stock Exchange.

But shares of the world's largest automaker are still down more than 60 percent since Wagoner took over as its CEO in 2000.

Toni Simonetti, a spokeswoman for the automaker, said GM is using "accelerated attrition tools" -- including early retirement plans -- to reduce employment in its non-union operations to better align its cost structure.

Robert Herta, a spokesman for GM who handles human resources issues, told CNN that the early retirement offer to some salaried workers was not new but rather part of an existing trend to reduce the white-collar work force at the world's largest automaker.

"2005 is no different than what GM has done in the past," Herta said. "It's a voluntary program."

The accelerated attrition program, as GM calls it, is being offered to salaried workers in GM's business units, which include finance, information technology, communications and marketing.

The Wall Street Journal reported Monday that the cuts could be as deep as 28 percent in certain departments at the world's largest automaker.

Simonetti would not confirm that number, but did say that the cuts in the specified departments could go as high as 20 percent in some cases.

GM warned on Wednesday that it expects a big loss in the first quarter due to sluggish sales and stiff competition in North America -- news that shocked Wall Street and sent its stock tumbling nearly 14 percent to a 12-1/2-year low.

For more on last week's profit warning from GM, click here.

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