DETROIT - General Motors stock plunged more than 22 percent to a 76-year low on Tuesday, a day after a group of GM executives disclosed they had sold shares in the struggling automaker, according to Reuters.

Six GM executives, led by former GM Vice Chairman and product chief Bob Lutz, disclosed on Monday that they sold almost $315,000 in stock and liquidated their remaining direct holdings in the automaker.

The stock sale underscores the extreme pressure on GM with less than three weeks remaining for the embattled automaker to win deals to slash debt and operating costs with its major union and bondholders to avoid bankruptcy.