A former worker at Wal-Mart is claiming the retail giant is running a sophisticated surveillance operation that targets employees, journalists, stockholders and critics. The worker, Bruce Gabbard, says the retail giant spied on employees, journalists, stockholders and critics of the company. We speak with the Wall Street Journal reporter who broke the story. [includes rush transcript]

Watching the watchdogs. A former worker at Wal-Mart is claiming the retail giant is running a sophisticated surveillance operation that targets employees, journalists, stockholders and critics. Bruce Gabbard was fired last month for intercepting and recording phone calls to and from a New York Times reporter. Gabbard told the Wall Street Journal he was part of a broader surveillance operation run out of Wal-Mart's Arkansas headquarters. Employees reportedly nicknamed their work area "The Bat Cave."

Gabbard also revealed that Wal-Mart infiltrated the group Up Against the Wal last year by sending a long-haired employee wearing a wireless microphone to one of the group's meetings. A Wal-Mart surveillance van was stationed outside the meeting in order to listen in to what was happening. Wal-Mart also reportedly closely monitored the internet and phone usage of employees at work. Managers received a list of email addresses and phone numbers with which their employees have communicated, and a list of Web sites visited. Wal-Mart also developed a system to read the personal emails of workers sent or received from private accounts such as Hotmail or Gmail.

After the Wall Street Journal story ran, Wal-Mart issued an apology -- but only to shareholders that were monitored under the surveillance operation.

We speak with one of the reporters who broke the story, Gary McWilliams.

• Gary McWilliams, reporter for the Wall Street Journal. He joins us from Houston.