Prosecutors have upgraded charges against a Hutchinson woman in the accidental death of her infant daughter.

Eighteen-year-old Brigit L. Hippen is charged with second-degree murder after her 3-month-old daughter died from hyperthermia and thermal injuries that investigators believe were caused by a handheld blow dryer.

Prosecutors had initially charged Hippen with involuntary manslaughter in the Feb. 23 death. She pleaded innocent in April.

The Hutchinson News reported Wednesday that despite the upgraded charges, prosecutors still say the death was accidental. No further details about what happened have been released.

Hippen’s attorney, David Harger, says he is frustrated that the Reno County District Attorney’s Office is charging a young mother with second-degree murder in an accidental death.