Kentucky detectives said Friday they are searching for a missing 13-year-old girl and her young sister who were taken by their mother after their father’s funeral.

“Law enforcement has reason to believe they could be in danger,” Detective Michael Wilson of the Allen County Sheriff’s Office told FoxNews.com.

Detectives said the 13-year-old, Jazzie Whitney, and her 11-year-old sister Cassie were last seen May 18 at a funeral for their father. Larry Whitney, 40, died of a stab wound to the chest two days earlier.

An arrest warrant accuses Melissa Scott, 38, of taking her daughters. She has been charged with custodial inference.

Investigators believe Scott ran off with the girls after child welfare workers took custody of the girls, Wilson said.

Investigators aren’t sure how the father died, Wilson said.

The detective said the death could have been accidental but an exact cause is pending an autopsy.

He said investigators want to talk to the mother and the girls about the stabbing, Wilson said.

Jerry Whitney told WBKO-TV his brother and Scott had a rocky relationship. He said he is worried about his nieces.

“I worry about their safety,” he said.

Wilson said anyone with information can call the Allen County Sheriff's Office at 1-270-237-3210.