Updated

Three men have been arrested on drug-related conspiracy charges following an investigation into the Dec. 1 shooting death of Charleston, W.Va., police Officer Cassie Johnson, authorities said Saturday, according to a report.

The arrests pertain to an alleged drug operation at a residence where the suspected gunman, identified by authorities as Joshua Phillips, allegedly went to buy drugs prior to the shooting of the police officer, WCHS-TV of Charleston reported. Investigators learned about the residence while investigating the shooting, the station reported.

None of the three conspiracy suspects faces any charges that are directly connected to the police officer's shooting death, Maryclaire Akers, an assistant prosecutor in Kanawha County, W.Va., told Fox News in an email.

The three conspiracy suspects were identified as Richard Chapman, 44; Herbert Sharp, 44; and Marshall Sharp, 24. The two Sharps are an uncle and nephew, Kanawha County Sheriff Michael Rutherford said at a news conference.

WEST VIRGINIA COP SHOT TUESDAY IS DEAD AFTER PULLED FROM LIFE SUPPORT; ORGANS TO BE DONATED

Officer Johnson, 28, responded to the location after a neighbor complained about a vehicle parking issue, WCHS reported. Soon after her arrival, Phillips allegedly shot the officer, who suffered severe wounds and died two days later in a hospital after being taken off life support, according to police.

Charleston, W.Va., police Officer Cassie Johnson died Thursday after being shot Dec. 1 during a confrontation with a suspect, authorities say.

Phillips was shot by Johnson during the confrontation and was hospitalized for treatment of his wounds, authorities said. He was considered detained and not arrested but was expected to face a charge of first-degree murder, WCHS-TV of Charleston reported.

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Meanwhile, Officer Johnson’s remains were transported to the Kanawha County Medical Examiner’s Office following organ donation, the station reported.

A memorial service and funeral for the officer have been scheduled for this coming Tuesday at the Charleston Coliseum & Convention Center, according to the Charleston Police Department.

Editor's note: This story has been updated from its original version with clarifying information provided by the Kanawha County Prosecutor's Office.