CITRONELLE, Ala. -- Searchers found human remains Saturday believed to be the daughter of an Alabama man already charged with murdering the girl and her younger brother, police said.

Mobile Police Maj. Kara Rose said search teams found the remains at 9 a.m., just half an hour after authorities began scouring the woods along six miles of a rural county road.

John DeBlase, 27, is charged with two counts of felony murder and two counts of corpse abuse. Skeletal remains found Wednesday in the woods of rural Mississippi are believed to belong to his 3-year-old son Chase.

The remains found Saturday are believed to be that of Natalie DeBlase, Rose said. Natalie would have turned 5 in late November.

Police have said DeBlase's common-law wife, Heather Leavell-Keaton, also is responsible for the killings. She has been charged with child abuse but has not been charged with murder. She was being extradited to Alabama and was expected to arrive there Sunday.

DeBlase's court-appointed attorney, Jim Sears, has said DeBlase maintains that he is innocent and that Leavell-Keaton killed the children. She has blamed DeBlase for the children's deaths. Police have said they both share responsibility for the slayings.

Mobile County Assistant District Attorney Jo Beth Murphree said Friday that authorities would soon be upgrading Leavell-Keaton's charges from child abuse to more serious aggravated child abuse counts. She also was to be charged with two counts of corpse abuse.

DeBlase had told police he dumped his daughter Natalie in the woods north of Mobile in March. He said he discarded the boy's body, dressed only in a diaper and stuffed into a plastic garbage bag, in Mississippi in June on or around Father's Day. Police say the children were killed separately, then immediately disposed of.

DeBlase and Leavell-Keaton were arrested last week on the abuse charges, and authorities began their search for the children's remains in Alabama and Mississippi over the weekend. Neither child had been seen for months.

An investigation into their disappearance didn't start until late last month after Leavell-Keaton sought a protective order against DeBlase in Kentucky, Levy said. She said in the Nov. 18 filing that DeBlase may have killed his children, and that she feared for her life because he was abusive. The couple had a child together this summer. That child is in state custody in Kentucky.

"I am afraid that he is going to do something to harm our daughter because of what he has done to the other children," she wrote.