A former Illinois bank official, now claiming whistleblower status, says bank officials replaced a loan reappraisal that he prepared for a Chicago property that was purchased by the wife of now-convicted felon Tony Rezko, part of which was later sold to next-door neighbor Barack Obama.

In a complaint filed Thursday in the Circuit Court of Cook County, Kenneth J. Connor said that his reappraisal of Rita Rezko's property was replaced with a higher one and that he was fired when he questioned the document.

Critics of Mr. Obama's dealings with Rezko charge that the senator may have gotten a deal on his property purchase, noting that Mrs. Rezko paid the full asking price for her property on an adjacent lot. Both of which were sold by a single seller. Mr. Obama bought his house for $1.65 million - $300,000 below the asking price.

When the property was sold, Mr. Obama knew Rezko was under investigation on fraud charges.