Miller, managing director of Citigroup's environment and social risk management team, was discovered on Tuesday in the bathtub of his upscale Greenwich apartment with his throat slashed. The NYPD told CNBC on Wednesday that the incident was likely a homicide, since a knife was not found.
But sources told Daily News on Thursday that investigators found a knife under the body, which may indicate that Miller cut his own throat and fell on top of the knife in the bathtub.
A NYPD spokeswoman declined to confirm the discovery of a weapon with CNBC and said the medical examiner will determine the final cause of death. The medical examiner did not immediately respond to CNBC's inquiry for comment.