STATEN ISLAND, N.Y. -- Police have a suspect in custody in connection with the killing of reputed Gambino mob boss Francesco (Franky Boy) Cali, 53, who was gunned down on Wednesday outside his Hilltop Terrace home, according to law enforcement sources.

A white male, 24, who is a Staten Island resident and was apprehended in New Jersey on Saturday morning, is being questioned in the Garden State about the murder, law enforcement sources told the Advance.

When he was apprehended, the suspect was in the vicinity of a blue pick-up truck, said police sources. He was reportedly found in Brick, N.J.

Detectives are working to match his fingerprints to Cali’s Cadillac SUV.

At this point, the motive is still to be determined.

One source told the Advance the killing initially does not appear to be mob related, but that some in the NYPD still believe it may be connected to the Mafia and it was premature to tell at this point.

Sources told NBC New York the man in custody is “a conspiracy theory type” who appears “a bit off.”

One theory being looked at is the individual wanted to date one of the mob boss’ relatives and Cali turned him down, according to the NBC New York report.

Moments before Cali was gunned down in front of his home on Hilltop Terrace, the suspect -- said by witnesses to be driving a blue pick-up truck -- backed into Cali’s parked vehicle, prompting the victim to exit his residence, according to police brass who held a press conference Thursday at NYPD headquarters.

“We know that there was a vehicle accident in front of the residence, and we believe the victim’s vehicle was struck,” said NYPD Chief of Detectives Dermot Shea said this week to the Advance. “(Cali) exits his house.. whether it was an altercation or a conversation remains to be seen."

Cali’s car “rocks significantly” from the impact of the other vehicle, Shea said. "So it takes some force to do that.”

Police said video surveillance of the encounter outside 25 Hilltop Terrace shows the suspect pull out a handgun about a minute into the conversation and fire 12 shots, at least six of the bullets striking Cali, who was pronounced dead at Staten Island University Hospital, Ocean Breeze, authorities said.

“In trying to elude gunfire he fled to rear area of his personal vehicle, and was trying to get underneath the truck,” Shea said.

A GLOBAL FIGURE

Though the low-key Cali was considered an under-the-radar figure compared to previous Gambino boss John Gotti, experts and historians identified him as a global figure and bridge between the American and the Sicilian mobs

Cali’s connection between the United States and Sicily finds its roots in his marriage with Rosaria Inzerillo, of the predominant Inzerillo family.

The Inzerillos were among the most powerful and wealthy families within the Sicilian Cosa Nostra, explained Maurizio Catino, visiting scholar at the department of sociology at New York University, who has written several books on the American and Sicilian Cosa Nostra.

“They were an important family in the Sicilian Cosa Nostra," said Catino “They were basically aristocrats.”

Things rapidly changed in the ‘80s when Salvatore Riina, the former boss of the Italian mafia, basically declared war on the Inzerillos as he was trying to gain power in Palermo.

Riina was so determined to dismantle the family that he once said that “nothing shall remain of them,” Catino explained.

Many Inzerillos decided to flee Sicily and start a new life in America, where they soon started doing business with the Gambino family.

Cali was indeed considered the bridge between the two countries.