SPRINGFIELD -- Francesco "Frank" Depergola has signaled his intent to plead guilty in an ongoing loansharking and extortion case, according to filings in U.S. District Court in Springfield.

Depergola, also known as "Sammy Shark," is one of five reputed mobsters from Greater Springfield who were arrested in August 2016 by federal agents and state police.

The men are accused of playing various roles in two separate incidents: allegedly extorting a local tow company operator, and allegedly making an illegal street loan to a man who later turned out to be an undercover FBI agent.

Depergola, 61, of Springfield, has been a longtime fixture on the local mob scene. He was the only eyewitness to the murder of slain mob boss Adolfo "Big Al" Bruno in 2003, and was later convicted in connection with a loansharking scheme that involved Bruno before his execution-style slaying.

Depergola was sentence to two years in federal prison in that case and was released in 2008.

"Everyone makes a mistake; I made mine," he told the sentencing judge in 2006.

He was arrested in the current case along with Ralph Santaniello, Gerald Daniele and Giovanni "Johnny Cal" Calabrese, all of Longmeadow, and Richard Valentini, of East Longmeadow.

The court records show Depergola has pleaded guilty to an "information" out of federal court in Manhattan, where he and Santaniello were charged in a sweeping dragnet of East Coast mobsters. That document outlines a "profit-sharing" extortionate loan scheme that culminated in the $30,000 loan to the undercover agent in August of 2014.

That took place at a Chicopee pizza shop at the behest of New York mob boss Eugene "Rooster" O'Nofrio, who has long had ties to Springfield underbosses, according to court records.

Charges brought in a parallel indictment in Springfield accuse the defendants of shaking down a local tow company operator for thousands of dollars in "street taxes" in 2013.

The alleged victim, identified only by investigators as Victim One, sought help from Massachusetts State Police and agreed to record subsequent meetings over their demands.

Santaniello and Calabrese were portrayed by the alleged victim as the primary aggressors who threatened to behead him if he didn't pay $20,000 up front and $2,000 per month thereafter.

Depergola seemed to play more of an elder statesman role, doing a softer, cautionary sell to convince Victim One to pay up for his own good, according to the recordings played in federal court during bail hearings.

Depergola advised: "They are going to come after you. ... These guys are vindictive mother-------, be careful what you say, what you do," according to the complaint.

All but Santaniello -- who recently struck a plea deal with prosecutors in New York -- have been released on bail pending the resolution of their cases.

The terms of Depergola's plea have not yet been filed with the court but a "Rule 20" motion logged in late August in New York will effectively transfer all the charges to Springfield, where his plea and sentencing hearings also will occur.

Valentini has a pending motion to suppress the recordings in the case. A trial date has been set for Dec. 11 before U.S. District Judge Timothy Hillman.