A New Jersey doctor who was accused of hiring a man to kill his wife after she threatened to expose the illegal prescription drug operation he ran out of his practice was found dead of an apparent suicide in jail, authorities said.

James Kauffman, who had been detained in a jail in a separate county from the one he was charged in because of what authorities said were threats against his life from other inmates, died Friday at the Hudson County Jail, according to the Atlantic County prosecutor’s office.

A law enforcement official familiar with the case said Kauffman suffocated himself using a strip of sheet tied to an upper bunk while his cellmate was away for a court hearing. He had lain down to make it appear as if he was sleeping and left behind a six-page suicide note, the official said.

Kauffman, 68, of Linwood, a small town outside Atlantic City, was charged with first-degree murder this month, more than five years after his wife, local radio personality April Kauffman, was found dead inside their home. Ferdinand Augello, who prosecutors said was a co-conspirator, is also charged with first-degree murder.

April Kauffman’s 2012 killing drew wide attention at the time and continued to garner news coverage after her daughter, Kim Pack, said publicly that James Kauffman was responsible.

The doctor was arrested in June after he brandished a handgun in front of officers who were executing a search warrant at his office in Egg Harbor Township, surrendering only after a standoff involving a hostage negotiator. Officials at the time said the arrest was not related to April Kauffman’s killing.

Prosecutors later outlined the prescription drug ring they said James Kauffman and Augello ran out of Kauffman’s office with the help of the Pagan Outlaw motorcycle gang.

April Kauffman’s killing came in response to a rancorous debate about divorce that included threats she made to expose the illegal drug operation, officials said.

“James Kauffman stated he would sooner kill April than grant the divorce and lose ‘half his empire,’ ” the  prosecutor’s office said.

Augello was solicited by James Kauffman to kill his wife, and he found another man, Francis Mullholland, a cousin of a Pagan associate and a member of the drug enterprise, to do the deed, officials said.

April Kauffman was found dead May 10, 2012. She was 47.

James Kauffman told officers who arrived that he had found her dead in the master bedroom on the second floor of their house, officials said.

Prosecutors said they think Mullholland shot April Kauffman and was paid for the job.

The drug enterprise, meanwhile, continued for years after the killing, until James Kauffman’s June arrest.

Mullholland died after what officials say was an accidental overdose in 2013, NJ.com reported.

“The investigation is continuing and we will have no further comment at this time,” the Atlantic County prosecutor’s office said in a statement.

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