Lafayette Parish Sheriff's Capt. Kip Judice said the cousin said he heard screams from the abandoned house and when he broke through the door he saw a man start to stab 29-year-old Bethany Arceneaux and fired his gun, CNN reported Saturday.
The cousin, whom the sheriff's department did not identify, fired several rounds but he told law enforcement personnel he wasn't sure if he hit the kidnapper in the dark house near Duson, Judice said.
Inside, officers found the body of Scott Thomas, who was the father of Arceneaux's baby and had violated a restraining order protecting her previously, Judice said. Arceneaux had several stab wounds and was hospitalized.
Arceneaux disappeared Wednesday night and was found Friday.
The sheriff's department determined the cousin acted within a state law that permits deadly force to prevent great bodily harm or death, but the case would be reviewed by the district attorney, Judice said.