VERNAL, Utah (AP) — A Utah woman has been accused of suffocating her 3-year-old stepdaughter.

Vernal police arrested 24-year-old Mckenley Yadon on Thursday on suspicion of aggravated murder and child abuse.

According to court documents, police were called to Yadon's home in mid-March to a report of the child choking.

Officers found the child not breathing and unresponsive and saw bruises on her head.

An autopsy determined the toddler died from asphyxia caused by smothering.

According to the documents, Yadon told police Thursday that she smothered the child using a blanket, and she had been planning to kill the child in the days leading up to the death.

Online court records do not list a defense attorney for Yadon who could comment on her behalf.

Yadon is being held in the Uintah County Jail.