A father whose missing children are believed to be dead told investigators he buried one of his young children in Mississippi in March, then buried the other in Alabama in June, police said Monday.

John DeBlase, 27, of Mobile, was being held on $206,000 bond. He is charged with child abuse and corpse abuse. The children's stepmother, Heather Leavell-Keaton, is jailed in Louisville, Ky. on child abuse charges. She will soon be extradited back to Alabama. The couple had been together since 2008 but they were not legally married.

Mobile police say Deblase has admitted burying his two children — 5-year-old Natalie and 3-year-old Chase — but claims Leavell-Keaton killed them. She is pointing the finger at him.

The children were last seen this summer, Mobile Officer Chris Levy said.

DeBlase has been trying to help investigators find the bodies, which led to searches over the weekend in rural areas of Alabama and Mississippi, but nothing was found, Levy said.

"He's placing the blame on Heather, and Heather's placing the blame on him," he said. "Both of them are ultimately responsible for the deaths."

Levy said DeBlase has had difficulty remembering the exact locations because the children were buried at two different times.

He said the father told investigators he buried the boy's body around the end of March in Mississippi, and later disposed of his daughter's body near the end of June in Alabama.

It remains unclear whether the children were killed at the same time.

"We're really trying to figure that out right now," Levy said. "Without the bodies, it's difficult to know."

DeBlase was arrested Friday in the Florida Panhandle, and does not have an attorney. He is set for arraignment on Wednesday. It was not immediately clear if Leavell-Keaton had a lawyer in Kentucky.

(This version corrects reference to Leavell-Keaton in second paragraph.)