Telecommunications giant WorldCom Inc. laid off nearly 6,000 workers worldwide in an effort to cut expenses and raise profit. Nearly every segment of the company was affected, said a source who spoke on condition of anonymity. The cuts accounted for about 7% of WorldCom's international work force of 90,000 and mark just the second time in the company's history it has let workers go. WorldCom, like AT&T and Sprint, has been battered by long-distance price wars and new competition from wireless phones and technology that enables calls to be placed over the Internet. Shares of Jackson, Miss.-based WorldCom fell 63 cents to close at $16.63 on Nasdaq.