Capt. Dale Call confirmed the passing of Hollister by phone Wednesday.
"We're limited in providing any other information and we are trying to make contact with all the family members at this point," said Capt. Call.
Hollister was convicted of killing Patricia Kimmi in 2011. His wife, Rebecca Hollister, was charged earlier this month in the case, accused of helping her husband avoid prosecution.
She is being held in the Atchison County Jail on a $100,000 bond, awaiting a preliminary hearing Monday.
Capt. Call would not release any further information about how Hollister died.
He said that information would depend on the next steps taken by the Department of Corrections.