A man accused with his girlfriend of kidnapping her baby and killing a social worker last week told reporters Wednesday he was responsible for the slaying as authorities returned the couple to Kentucky to face charges.

When a throng of reporters greeted the couple Wednesday evening, Christopher Wayne Luttrell "apologized for all the people he hurt, all his family and friends," said Henderson police Sgt. John Nevels, one of two officers who escorted Luttrell.

When asked if he killed social worker Boni Frederick, Luttrell replied, "Yes, ma'am," according to Nevels and reporters who were present.

FBI agents arrested Luttrell, 23, and Renee Terrell, 33, on Oct. 19 in a trailer where they sought shelter after the car they were driving — Frederick's station wagon — broke down near Godfrey, Ill., about 30 miles north of St. Louis.

Authorities allege the couple fled three days earlier after killing Frederick, 67, and abducting Terrell's 10-month-old son, Saige. Frederick had taken the boy to Terrell's home in Henderson for a visit.

The baby was found unharmed and has been returned to foster parents in Union County, Ky.

Federal prosecutors in Kentucky initially charged the couple with fleeing to avoid prosecution on kidnapping charges, but have dropped their charges so state authorities could prosecute the two on felony murder, kidnapping, robbery and theft charges, Nevels said.

Luttrell and Terrell were escorted in separate vehicles from Illinois, Nevels said.

Luttrell "talked all the way back," discussing everything from police who had arrested him in the past to rules of prisons where he served time for burglaries and thefts, Nevels said. "We just mainly listened."

Nevels declined to say what, if anything, Luttrell had to say about the slain social worker.

Terrell and Luttrell were expected to be arraigned by video in a local court this week, with a preliminary hearing expected next week, Nevels said.

Terrell's infant son had been removed from her custody when he was 13 days old because of neglect, police said. Police also said courts were in the process of permanently removing Terrell's parental rights before Frederick was slain.