Missouri investigators are working with an unnamed Oklahoma sheriff’s office to find the remains of a 4-month-old girl believed buried in Oklahoma.

The infant is one of three babies whose father is charged in connection with their deaths.

A 47-year-old father from Harrisonville, Mo., was charged Jan. 23 in Cass County, Mo., Associate Circuit Court with second-degree murder, endangering the welfare of a child, second-degree statutory rape, two counts of incest and two counts of accessory abandonment of a corpse.

He is accused of molesting and impregnating his daughter over several years.

The victim gave birth to a girl March 24, 2004, in Oklahoma when she was 15, according to a probable-cause statement. The infant died July 8, 2004.

The victim told authorities when the infant died, she wrapped the child in a blanket. She along with her father, her mother and sisters drove to Oklahoma and buried the baby in a box with silicone around the lid, according to the statement.

“We are working with a county sheriff’s office in Oklahoma,” said Cass County, Mo., sheriff’s Cpl. Kevin Tieman.

Tieman declined to give any details or identify the county, citing an ongoing investigation, but did say this week’s ice storm slowed the investigation.

Jessica Brown said the Oklahoma State Bureau of Investigation has not been asked to help in the search.

The father is due in court in March.

The victim told authorities she had been having sex with her father since she was 13, and he was the father of her four children.

The story came out in October after the victim’s younger sister told authorities, according to the probable-cause affidavit.

The father confessed to authorities he molested his daughter and that two of the children were his. He said he delivered two of the babies with the assistance of his wife, and she delivered two babies with his assistance.