The body of Sandy Hook Elementary School shooter Adam Lanza was claimed last week by someone who didn't wish to be identified, an official said Monday.
"The person that claimed the body requested to remain anonymous," said Linda Sylvia, secretary for Connecticut's chief medical examiner.
The body was claimed Thursday, she said, declining to release further details.
On December 14, Lanza, 20, took guns belonging to his mother, Nancy, and shot her as she slept in her bed. Then he went to the school in Newtown, Connecticut, where he gunned down 20 children and six staff members before killing himself.
It was one of the worst mass shootings in U.S. history.
Lanza's father, Peter, was questioned by authorities after the shooting, as was his 24-year-old brother, Ryan.
Authorities have offered few details about Lanza. He had no known criminal record, authorities have said.
A relative told investigators that Lanza had a form of autism, according to a law enforcement official, who spoke under condition of anonymity due to the sensitive nature of the investigation. CNN has not been able to confirm independently whether Lanza was diagnosed with autism or Asperger's syndrome, a higher-functioning form of autism.
Geneticists are now studying Lanza's DNA, a spokeswoman for the University of Connecticut Health Center said last week.
The geneticists were asked to join the investigation by the state medical examiner's office, spokeswoman Carolyn Pennington told CNN. She said that there is no specific genetic marker the team is looking for, and that lab results and a complete analysis of the DNA "are not expected for several weeks ... probably the end of January."
While experts agree that there are genetic components to many mental illnesses, there are hundreds, perhaps thousands, of genes involved. Most believe that no single gene or mutation alone could foretell violent acts like those committed by Lanza.
CNN's Nick Valencia contributed to this report.
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