BEND, Ore. -

A man accused of killing a 78-year-old woman at her home near Sisters changed his plea Wednesday to guilty of murder.

A Deschutes County Circuit Court judge sentenced 30-year-old Joshua Jokinen to life in prison with no parole for 25 years.

Jokinen apologized in court to the family of Carolyn Burdick but said he had no idea why he killed her.

The Bulletin reports he hit the woman on the back of the head with a shovel in August after delivering a load of firewood to her horse-breeding farm.

Jokinen pleaded guilty without reservation or bargaining with prosecutors. He had been scheduled for trial next week.