(CNN) -- Authorities have wrapped up their search at the home that once belonged to New York gangster James "Jimmy the Gent" Burke after finding material that "may be human remains" under the floor, a law enforcement source with knowledge of an investigation at the home said Thursday.
Investigators at Ozone Park in Queens finished the search Wednesday night for human remains possibly connected to a case that happened before 1996, said the source, who spoke on condition of anonymity.
It will be a few days before the FBI learns from forensic testing by the medical examiner's office if the remains are human, the source said.
According to public records, the house is now owned by Burke's daughter, Catherine Burke, who declined Tuesday to comment to CNN.
James Burke died in 1996. According to his obituary in the New York Times, he was serving a 20-years-to-life sentence in a New York prison when he fell ill with cancer.
Robert De Niro played Burke as Jimmy Conway in the 1990 Martin Scorsese classic mafia film "Goodfellas," and Burke is likely best known as the alleged mastermind of the 1978 Lufthansa heist, an $8 million robbery at John F. Kennedy International Airport, which was the largest robbery in history at the time.
But the source said that Burke and his cohorts, closely associated with top members of the Lucchese crime family, also were allegedly involved in a number of other activities -- so the search in Queens may not be related to the Lufthansa heist.
Jim Margolin, a spokesman for the FBI's New York office, told CNN on Tuesday, without elaborating, that investigators were "conducting a search at a home in Queens in connection to an investigation."