OKMULGEE COUNTY, Oklahoma - An Okmulgee County woman accused of killing her 18-year-old son and shooting her two teenage daughters told investigators "some part of me thought I was saving them," according to an affidavit of probable cause.

Amy Leanne Hall is accused of first-degree murder and two counts of shooting with intent to kill. Authorities said she shot her children in their home in Nuyaka, which is in the Beggs school district.

An investigator spoke to Hall in an interview room, court records show. Hall said she shot her son, Kayson, in the head while he slept in his bed. 

Hall said she then fired at her daughters who were sleeping in a bed together. She shot one girl in the head, the affidavit states, then "shot at" her other daughter, striking the wall with at least one bullet.

The younger daughter ran to the bathroom and began to cry, telling her mother that it would be OK and eventually taking the pistol from her mother's hand, the affidavit says.

Hall then left the house, according to the affidavit. 

Documents show Hall also told the investigator she intended to kill herself but denied planning to kill a friend of her son's who was spending the night.

She said more than once that she didn't know why she did it, then she mentioned her ex-husband and said, "some part of me thought I was saving them," the affidavit states.