Thomas Gilbert, the 70-year-old founder of Wainscott Capital Partners, was found shot dead in his Manhattan apartment Sunday night and police took his son Tommy Gilbert, 30, into custody around 10:45 p.m. Sunday, authorities said.
Detectives believe the elder Gilbert was killed by his son, who then left the murder weapon -- a .40 caliber Glock 22 -- in the bedroom to make it look like a suicide.
"The gun was resting on his chest with his left hand covering it," NYPD Chief of Investigations Robert Boyce said at a press conference. He desccribed it as a "staged crime scene."
Police said the son entered his parents' Beekman Place home Sunday afternoon and asked his mother to get him a sandwich.
Boyce said that the mother "had a bad feeling" after leaving the two men alone together and decided to return to the apartment, but when she came back she found her husband shot in the head in his bedroom.
Boyce said that the woman told police her son's address and they immediately ordered a search warrant, but waited until they saw lights go on inside the residence before entering. Inside they found "a substantial amount of physical evidence" including loose rounds of bullets and two magazines that matched the weapon that had allegedly been placed on his father's chest.
Investigators told ABC News that the father recently discussed no longer paying his son's rent. They also say he discussed reducing his weekly allowance from $400 per week to $300.
Public records show that Tommy Gilbert was arrested in Southampton in September for second degree criminal contempt for allegedly violating an order of protection, though no specifics about the restraining order were released. He has not yet entered a plea in this case and a hearing is scheduled for Feb. 2.
He was also arrested in May 2007 on drug charges but no further information about the status of those two cases were publicly available.
A spokesman for Princeton University confirmed that both Gilberts graduated from the school. The father graduated in 1966 and the son graduated in 2009.
The son also attended Deerfield Academy and graduated there in 2003.
Tommy Gilbert's activity after his college graduation has not yet been revealed publicly.
WABC's Mark Crudele contributed to this report.