Toms River, N.J. -- The man charged with killing the reputed boss of the Gambino crime family wrote pro-Donald Trump slogans on his hand and flashed them to journalists before a court hearing Monday.

Anthony Comello, 24, was arrested Saturday in New Jersey in the shooting death of Francesco "Franky Boy" Cali last week in front of his Staten Island home.

While waiting for a court hearing to begin in Toms River, New Jersey, in which he agreed to be extradited to New York, Comello held up his left hand.

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On it were scrawled pro-Trump slogans including "MAGA Forever" -- an abbreviation of Mr. Trump's campaign slogan "Make America Great Again." It also read "United We Stand MAGA" and "Patriots In Charge." In the center of his palm he had drawn a large circle. It was not immediately clear why he had done so.

Anthony Comello displays writing on his hand during his extradition hearing in Toms River, N.J., on March 18, 2019 Seth Wenig / AP

Comello's lawyer, Brian Neary, wouldn't discuss the writing on his client's hand and wouldn't say whether Comello maintains his innocence. Asked by reporters after the hearing what was on Comello's hand, Neary replied, "Handcuffs."

He referred all other questions to Comello's Manhattan lawyer, Robert Gottlieb, who said in an emailed statement his client has been placed in protective custody due to "serious threats" that had been made against him, but offered no details about them. Ocean County officials couldn't immediately be reached after hours on Monday.

"Mr. Comello's family and friends simply cannot believe what they have been told," Gottlieb said. "There is something very wrong here and we will get to the truth about what happened as quickly as possible."

The statement didn't address the writing on Comello's hand, and a lawyer from Gottlieb's firm declined to comment further Monday evening.

Comello sat with a slight smile in the jury box of the courtroom Monday afternoon as dozens of reporters and photographers filed in. When they were in place, Comello held up his left hand to display the writings as the click and whirr of camera lenses filled the room with sound.

During the hearing, Comello didn't speak other than to say, "Yes, sir" to the judge to respond to several procedural questions.

Cali, 53, was shot to death last Wednesday by a gunman who may have crashed his truck into Cali's car to lure him outside. Police said Cali was shot 10 times.

Federal prosecutors referred to Cali in court filings in 2014 as the underboss of the Mafia's Gambino family, once one of the country's most powerful crime organizations. News accounts since 2015 said Cali had ascended to the top spot, though he was never charged with leading the gang.

His only mob-related conviction came a decade ago, when he was sentenced to 16 months in prison in an extortion scheme involving a failed attempt to build a NASCAR track on Staten Island. He was released in 2009 and hasn't been in legal trouble since then.

Police haven't yet said whether they believe Cali's murder was a mob hit or whether he was killed for some other motive.

Privately, police sources told CBS New York it appears Comello acted alone, angry that Cali didn't want him to date his niece, but publicly, the New York Police Department said nothing is off the table.

"Let me reiterate it again, this is far from over," NYPD Chief of Detectives Dermont Shea said Saturday.

"I do not believe this man acted alone," former FBI agent and organized crime expert David Shapiro told CBS New York. "I would be shocked if there weren't material assistance provided elsewhere."

When asked if the shooting might have been planned with others, Shapiro echoed the concerns voiced by NYPD investigators.

"I think it's a strong possibility," he said.

Police sources say Comello was a hot-head and a marijuana user who had a crush on the victim's niece, and he was angry that Cali told him he wasn't good enough for her.

The last Mafia boss to be rubbed out in New York City was Gambino don "Big Paul" Castellano, who was assassinated in 1985.