More than five years after a witness in a Medicare fraud case was gunned down in Gentilly, federal prosecutors have charged the man against whom he was supposed to testify of involvement in a murder-for-hire plot.

An 11-count indictment unveiled Tuesday alleges that Louis Age Jr., his son and three other men conspired to kill Milton Womack in July 2012 to stop him from testifying in federal court.

Nevertheless, prosecutors managed to convict Age of defrauding the federal government of $17.1 million. A judge sentenced the former owner of South Louisiana Home Health Care to 15 years in prison in 2013.

“It’s been a long-simmering and probably a thorough investigation,” said Michael Fiser, a defense attorney who represented Womack before his death. “Looks like they’ve finally done it.”

The indictment, which was issued under seal on Aug. 17, also charges Age’s son Louis “Big Lou” Age III, Ronald “Tank” Wilson Jr., Kendrick Johnson and Stanton “Nan Nan” Guillory with roles in a plot to kill Womack.

All the defendants have been taken into custody. Guillory has pleaded not guilty to all counts. Louis Age Jr., Louis Age III and Johnson are to be arraigned Wednesday.

Prosecutors first obtained an indictment against Guillory — an alleged associate of the notorious “110’ers” street gang — last year. The new superseding indictment adds the other defendants.

Guillory was charged as the driver in the notorious May 29, 2012, shooting of 5-year-old Briana Allen and Shawanna Pierce in Central City. Authorities said he was a member of the “Young Mafia Fellaz” group, which linked up with the allied 110’ers gang as they sought to take out members of the Young Melph Mafia. The young girl was killed instead.

Guillory has yet to have his day in court on a host of state charges connected to the Allen shooting. His next appearance is set for Oct. 19, according to court records. His defense attorney could not be reached on Tuesday.

The new indictment adds new names but scant details to what is known about an allegedly tangled plot to kill Womack, a guitarist who attended Alcee Fortier High School in his youth.

The Ages, Wilson and Johnson are all accused of “procuring” the death of Womack, while Guillory is accused of committing the killing in expectation of payment.

Prosecutors have yet to reveal how they think Guillory, a 23-year-old alleged small-time gangster, linked up with Louis Age Jr., a 68-year-old former health care executive.

Prosecutors said in the state racketeering indictment of the 110'ers group that Guillory “and two unindicted co-conspirators, R.J. and B.M., committed the murder of M.W., while armed with a 9mm firearm.”

That allegation and those initials line up with Raheem Jackson and Brian Marigny, two men who testified at the 110'ers trial. Jackson and Marigny are not listed by name in the new charges, and their plea agreements with federal prosecutors appear to remain under seal.

Womack, 60, had just agreed to cooperate with the government in the massive Medicare fraud case against South Louisiana Home Health when he was shot multiple times in a red Dodge van in the 2700 block of Verbena Street.

Prosecutors alleged that he took $300 kickbacks in order to recruit patients for the company’s unnecessary home health care services. He was supposed to enter a guilty plea in the case on July 30, 2012, three days after he was killed.

Fiser said he has long suspected that the killing was linked to Womack’s decision to testify. Prosecutors questioned Age about the killing when he took the stand at his trial, but they had not formally accused him until last month.

Age was also questioned about whether he offered Womack money in an effort to dissuade him from testifying. That allegation lines up with one count in the indictment, which states that Age, his son and Johnson offered “financial benefits” to a potential witness if that person agreed to take the fall for some crimes and “falsely exonerate certain parties” of other crimes.

The three men also “threatened and intimidated” that witness when they learned that he had offered to cooperate with the government, according to the indictment.

Another unnamed witness in the health care fraud case did receive cash and other benefits in exchange for silence, according to the indictment.

Louis Age’s daughter, Ayanna Age Alverez, testified at the trial, and the new indictment makes allegations that could involve her.

The indictment states that the Ages and Johnson “did cause a potential witness to permanently leave the family home when they learned that the person was cooperating with law enforcement,” although it does not say whether the witness was Ayanna Age Alverez.

Two of the defendants are also accused of lying to investigators about Womack's killing. The feds said that Johnson lied when he told a grand jury in August 2012 that he knew nothing about Womack's death, and that Louis Age III lied to an FBI agent about a cellphone used in the murder conspiracy.

Follow Matt Sledge on Twitter, @mgsledge. | (504) 636-7432