Haspil is expected to be charged in a criminal complaint with second degree murder and other crimes.
The headless torso of Saleh, with all four of his limbs severed, was discovered next to an electric saw Tuesday, July 14, inside his Lower East Side apartment in Manhattan.
Law enforcement sources told The Daily Beast that detectives began looking at Haspil as a suspect after finding messages where Saleh had accused him of stealing tens of thousands of dollars over a period of time.
He was riding up to his $2.2million apartment beside a man wearing a "ninja-like" hood who had followed him into the lift, the newspaper said quoting sources.
The killer's work dismembering the body was interrupted when Saleh's sister entered from the building's lobby, another official said, prompting him to flee through the apartment's back door and into a stairwell before the sister arrived.
Harvard, MIT to argue foreign student ban will harm universities, public health
Colleges are asking the court to block the rule as quickly as possible, saying it's already being used to turn students away. Students already in the US would have faced deportation if they didn't transfer schools or leave the country voluntarily.
As Saleh turned to walk to his apartment, which occupied the entire seventh floor of the 10-story building, the assailant stepped behind him.
The medical examiner ruled the death a homicide after an autopsy found the cause of death was multiple stab wounds to the body.
Mr Saleh, who was born in Saudi Arabia to Bangladeshi immigrant parents, was described as a nice and loving person who loved gadgets and video games.
The gruesome killing shocked neighbors and the tech and venture capital worlds, where Saleh, a founding partner at Adventure Capital, cultivated a reputation as an energetic, creative businessman who specialized in direct investment in developing nations. More recently, he was the CEO of Gokada, a motorcycle ride-sharing and delivery company based in Nigeria, which has faced financial setbacks and recently laid off most of its staff.
Investigators had been exploring whether the killing could have been related to Saleh's business dealings.
"Fahim was a great leader, inspiration and positive light for all of us", the company said on Twitter.