Amazon.com said Friday that it laid off 150 workers (2 percent of its workforce)--the largest employment cutbacks ever announced by the Internet pioneer.

The cutbacks--at a high- flying company whose founder, Jeff Bezos, only recently was named Time magazine_s "person of the year"--came as a surprise. They will be across the board, but mainly at Amazon_s Seattle headquarters, the company said. Amazon_s stock fell sharply in trading Friday, down as much as 10 percent. "We regularly review the mission of the company and make sure we have the right skills to carry out the jobs," spokesman Bill Curry said. Curry said the cutbacks stem from an "ongoing process" of reviewing the Internet retailer_s organizational structure. He would not confirm or deny whether more layoffs are imminent. The layoffs come just five days before Amazon will report fourth-quarter earnings. The results will be closely watched by Wall Street. Many analysts, for example, will be watching to see whether Amazon turned a profit in its U.S. book business for the latest quarter, as promised.