Prosecutors must reorganize their case against a man accused in a fatal shooting on the Big Island after two witnesses refused to testify.

Acting on advice from their attorneys, Sharina Pavao and Christian Alameda invoked their Fifth Amendment rights against self-incrimination Friday at a preliminary hearing for Eric Fontes Jr., who is charged with murder in the death of 59-year-old Barton Bumatay.

Authorities say Bumatay was shot twice in the head at his home in a Puna subdivision early New Year’s Day. His dismembered body was found Jan. 23 in two separate locations in the neighborhood.

Court documents say Alameda and another witness, Shannon Souza, told police that 34-year-old Fontes had forced them at gunpoint to help dispose of Bumatay’s body. The state had planned to call Souza to the stand Friday, but he did not have an attorney at the time.

Pavao told police Fontes had bragged about the killing and making Alameda and Souza chop up the body, according to the documents.

Deputy Prosecutor Kevin Hashizaki said he was not surprised by the witnesses’ decision not to testify, as they and Souza have not been offered immunity in exchange for their testimony.

“That is something our office is going to have to look at in terms of the risk and reward,” said Hashizaki. “We just need to be sure that they are not involved in any way in the homicide if we offer them any sort of immunity.”

The state’s case will depend on how it can work with the witnesses’ attorneys, Hashizaki said.

Cody Frenz, Fontes’ attorney, declined to comment Friday.