The New York Post digs deeper into the CBS News investigation into CBS News employee Joe Halderman which was first reported Tuesday in the New York Observer. CBS Evening News investigative correspondent Armen Keteyian, who knows Halderman, is said to be investigating the story.

“How is this good?” asked a “48 Hours” source about the “Evening News” probe. But an “Evening News” source said the probe was spurred by a desire to avoid sitting on the sidelines while other media feast on the scandal. “CBS cannot be seen to be burying its head in the sand,” the source said.

The Post reports Keteyian has already conducted several background interviews “in the news department.”

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