WASHINGTON (CNN)  -- First lady Michelle Obama's father is not buried in the Chicago-area cemetery where investigators say hundreds of graves have been dug up in a scheme to resell the burial plots, a spokeswoman said Tuesday.



First lady Michelle Obama's father is not buried in the Chicago-area cemetery where graves were disturbed.



The announcement followed an earlier, mistaken statement by the first lady's communications director, Camille Johnston. Johnston later said that Obama's father, Fraser Robinson III, was buried in Lincoln Cemetery in suburban Alsip, Illinois, not the Burr Oak graveyard now at the center of a criminal investigation.



"There has been some confusion that has been cleared up," Johnston said.



Robinson, who worked as a pump operator for the Chicago water department, died in 1991 after a long struggle with multiple sclerosis. Lincoln Cemetery is about 2 miles from Burr Oak.



Four people face felony charges in the investigation surrounding Burr Oak Cemetery in Alsip, Illinois.



Authorities said last week that about 300 graves had been disturbed as part of the scheme, but that number is expected to rise.



Cook County Sheriff Thomas Dart said his office has received more than 55,000 requests for information from families with loved ones buried in Burr Oak. But he said many of the cemetery's records are in rusted cabinets filled with decaying file cards.



"Most of the file cards have rotted together," he said. "They're covered in mold, and they've rotted together."



In addition, some of the cemetery's books are missing pages, and others are known to have been altered, "So this has made it incredibly difficult for us to give accurate information," Dart said. His office asked a court Tuesday to appoint a receiver to manage the graveyard, which he said has been run by his office since last week.



Among others buried in the 150-acre graveyard are civil rights martyr Emmett Till, blues pioneer Willie Dixon, jazz and blues singer Dinah Washington and several Negro League baseball players. Cemetery groundskeepers told investigators that Till's grave was not among those disturbed, but the identities of other remains dug up have not been disclosed.



Carolyn Towns, an office manager for the cemetery, and gravediggers Keith Nicks, Terrance Nicks and Maurice Daley have each been charged with dismembering a human body. The felony charge carries a sentence ranging from six to 30 years, authorities said.



Authorities began investigating the cemetery about six weeks ago after receiving a call from its owners, who said they suspected "financial irregularities" regarding the business, Cook County Sheriff Thomas Dart told CNN last week. He said the owners are not believed to be involved in the alleged scam.



CNN correspondents Dan Lothian and Elaine Quijano contributed to this report.
How many graves have been disturbed? where Authorities said last week about 300 graves? Where is Fraser Robinson III buried? what Official corrects confusion, says Michelle Obama's dad?
hundreds of Burr Oak Cemetery Lincoln Cemetery in suburban Alsip, Illinois, first lady's communications director, Camille Johnston.
question: How many graves have been disturbed?, answer: hundreds of | question: where Authorities said last week about 300 graves?, answer: Burr Oak Cemetery | question: Where is Fraser Robinson III buried?, answer: Lincoln Cemetery in suburban Alsip, Illinois, | question: what Official corrects confusion, says Michelle Obama's dad?, answer: first lady's communications director, Camille Johnston.