Investigators say a veteran defense attorney who once represented the mobster immortalized in "Goodfellas" has plotted to murder witnesses in another case.

Robert Simels, 61, was arrested Tuesday on charges of witness tampering and obstruction of justice. He was released on $3.5 million bond.

A criminal complaint accuses Simels of plotting to "eliminate" prosecution witnesses against an alleged drug trafficker.

His attorney, Gerald Shargel, called the allegations false.

"Bob Simels is well-known as a tenacious, effective and highly capable defense lawyer and he was doing his work," Shargel said Wednesday.

Drug Enforcement Administration investigators allege that in May, a cooperating member of a paramilitary organization in Guyana known as the Phantom Squad learned that Simels wanted to talk to him. Simels was representing a Guyanese businessman, Shaheed "Roger" Khan, who was charged with running a cocaine smuggling operation that was protected by the Phantom Squad.

The DEA says that during conversations over the summer, some secretly recorded, Simels asked the cooperator to help him locate potential government witnesses and pondered what to do when they were found. The attorney "discussed a range of options, from offering them money to murdering their family members," the criminal complaint says.

In one conversation recorded in May about bribing an unnamed witness, the cooperator suggested the witness "might suddenly get amnesia" if paid enough money.

"That's a terrible thing, but if it happens, it happens," Simels responded, according to the complaint. Later in the same meeting, the lawyer remarked, "Obviously, any witness you can eliminate is a good thing."

Simels is known for representing Henry Hill, whose exploits were the basis of the 1990 Martin Scorsese mob film "Goodfellas," and Kenneth "Supreme" McGriff, a gang leader accused of funneling drug money into Murder Inc., then a chart-topping rap music label.

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