The person spoke on condition of anonymity to The Associated Press on Saturday because the deal has not been announced.
Financial terms were not available.
The 31-year-old Harper has been a mainstay at strong safety in New Orleans for the past eight seasons and went to the Pro Bowl in 2009 and 2010. He only played in five games last season due to injuries.
Harper is expected to fill the void left by Mike Mitchell, who signed earlier this week with the Pittsburg Steelers.
The 6-foot-1, 200-pound Harper has 17 career sacks, the most by any defensive back since 2006. He's also forced 13 fumbles.
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