MOUNT DESERT – A witness has died of natural causes in a murder case involving a caregiver accused of using a ceramic gargoyle to bludgeon to death a retired professor.

Dari C. Burke, 63, died last week from lupus, according to an obituary published Thursday in the weekly Bar Harbor Times newspaper.

Lupus is a frequently fatal disease that causes a person’s immune system to attack otherwise healthy tissue.

A friend of Burke’s, Jacqueline Evans of Southwest Harbor, had hired murder suspect Michelle Mills in late 2005 to help care for Burke as Burke’s health deteriorated.

Last January, nine days after Evans and Mills allegedly argued over money, Evans, 83, was found unconscious and bleeding profusely on the kitchen floor of her Alder Lane home. Mills is accused of bludgeoning Evans on the head with a ceramic gargoyle statue.

A retired mathematics professor from Wellesley College in Massachusetts, Evans died from her injuries two days later.

Burke had told police that Evans paid Mills $11,000 between Thanksgiving 2005 and the end of that year and that on Jan. 11, 2006, Evans and Mills had argued over the phone about additional payments, according to court documents.

Mills was fired from her duties helping Burke on that same day.

Mills, 37, later told police Evans had promised to pay her another $11,000 after the first of the year.

Burke, a trained professional chef, was in Mount Desert on Dec. 17 when she “died suddenly from complications associated with” lupus, according to the obituary. She would have turned 64 the following day.

A native of Birmingham, Ala., Burke regularly attended Somesville Union Meeting House in Mount Desert and “rescued” many animals during her lifetime, the obituary said. She is survived by a son in Connecticut and a daughter in Florida.

Mills was arrested in June after she was secretly indicted by a Hancock County grand jury on a charge of murder. She had moved from Southwest Harbor to Bangor when she was arrested on the front steps of her York Street apartment by two state troopers.

She has been in custody since her arrest in June. She is being held at the Hancock County Jail in Ellsworth with a set bail of $500,000 in property or $250,000 in cash.

Because of the pending case against Mills, Deputy Attorney General William Stokes declined to comment Thursday, either specifically about Burke’s death or about the effect the death of a potential witness could have on a criminal trial.

Assistant Attorney General Andrew Benson, the prosecutor in the case, also declined to comment Thursday.

Mills’ attorney, Jeffrey Silverstein of Bangor, indicated Thursday that he had not heard of Burke’s death. “I don’t have a comment,” he said.