Police are now investigating the matter and have yet to arrest anyone in connection.
Cali was named head of the family in summer 2013, DNA Info reported at the time, taking over total control of the more than 750-person organization. "EMS also responded to the scene and transported the victim to Staten Island University North, where he was pronounced deceased".
They said distraught family members ran outside after the shots were fired.
Shea said the mob boss emerged from his home around 9:15pm. after the gunman backed his pickup into Cali's Cadillac SUV, damaging it.
The last crime family boss to be shot in NY was Paul Castellano, who was also a Gambino crime boss.
The reputed boss of New York's Gambino crime family was left riddled with bullets outside his home on Staten Island, an old-school hit akin to the storied executions of 20th-century mafia dons.
His only criminal conviction came in 2008, when he pleaded guilty to an extortion conspiracy charge resulting from a failed bid to build a NASCAR track on Staten Island years earlier. Gotti's brother Gene Gotti spent 29 years in prison for heroin distribution, but he got out in September 2018, leading to speculation as to what that could mean for the future of the organization.
NY media say it is the first targeted killing of a mob boss in the city since 1985.
He was assassinated outside Sparks Steakhouse in Manhattan in 1985.
Cali joined the family when it was still one of the most powerful criminal organisations in the US. "Very surprising, but I guess old habits die hard".
"Frank Cali was a pretty likeable guy, and also this is not a way the mob would kill one of their own", he said.
After all, it had been 34 years since a Mafia don like him had been "whacked" on the streets of NY.
Last October, Bonanno crime family associate Sylvester Zottola, 71, was gunned down at a Bronx McDonald's drive-thru as he waited for a coffee. For that, he got 16 months in prison before he was released.
Weiss explains that the younger Gotti and Cali had often clashed 30 years ago, and upon his return, reignited their feud.
A witness said that his family members rushed outside after Cali was gunned down.