Cali spent time in prison from 2008 to 2009 on extortion charges related to a planned NASCAR race track on Staten Island.
Pandrella, 59, is accusing of shooting Zito in his own home and stealing money from him - before returning to the scene of the crime hours later to grieve with the older man's family. News accounts since 2015 said he had ascended to the top spot.
Castellano was the leader of the Gambino crime family when he was shot to death outside Sparks Steakhouse in Midtown Manhattan in 1985.
The New York Daily News stated that a family member called 911 and said Cali was run over before he was shot; one witness told the Daily News, "There were like six shots, and then there were three more".
A Gambino family memeber has spoken out after the death of Gambino crime boss, Frank Cali, and paid tribute to the man he says all the kids looked up to.
The killing of Francesco "Franky Boy" Cali in New York City this week has shed light on past mob-related in hits in America. In 2002, Gotti died in prison after testimony from his underboss "Sammy the Bull" Gravano, who turned federal witness.
"The Gambino crime family during Castellano's reign was the largest criminal organization in the US, with law enforcement estimating it had some 250 "'made" members" and "more than 550 lower-ranking "associate' members".
Cops retrieve evidence from the scene where Mob boss Francesco Cali was clipped late Wednesday. THE ASSOCIATED PRESS
His uncle through marriage, John Gambino, was a Gambino captain and served on the family's ruling panel, said Probation.
That hit was ordered by Gotti, who later took over the family until being convicted of racketeering and Castellano's murder in 1992.
Probation asked that Cali, during his supervised-release period, only be allowed to associate with his uncles and brother-in-law at family social functions, such as weddings and holidays, and then, only with departmental approval.
The killing of a Mafia "Don" is a serious matter within the criminal organization.
Last October, Sylvester Zottola, 71, reportedly of the Bonanno crime family, was gunned down at a McDonald's drive-thru in the Bronx.
Gambino headed the organization until 1976, when he handed power over to his brother-in-law Paul Castellano.
Witnesses told NY media outlets that they heard a number of shots before a blue pickup truck fled the area.
In that case, authorities intercepted conversations shedding light on his quiet underworld command.