A Kentucky couple suspected of kidnapping the woman's 9-month-old son after a social worker, who was later found dead, brought the child for a visit were arrested Thursday night in Illinois, an FBI official said. The infant was found unharmed.

FBI agents arrested Renee Terrell, 33, and her boyfriend, Christopher Wayne Luttrell, 23, in a rural area near Godfrey about 8:30 p.m., said FBI spokesman Marshall Stone. The boy, Saige, was found in the same place, he said.

Sgt. John Nevels of the Henderson, Ky. Police Department was on the scene and said the couple were "caught ... hiding in a camper."

Earlier in the day, the FBI had issued warrants for Terrell and Luttrell for unlawful flight to avoid prosecution on state kidnapping charges, according to Tracy Reinhold, special agent in charge of the FBI in Kentucky.

The baby had been removed from Terrell's custody when he was 13 days old because of neglect, according to police. On Monday, social worker Boni Frederick, 67, took the boy to his mother's Henderson, Ky. home for a visit.

Frederick was found beaten to death at the house later that day, and the baby, his mother and Frederick's station wagon were gone, authorities said.

Henderson police Detective Ron Adams said Frederick's purse was found near Mount Vernon, Ill.

A neighbor, Jean Davis, had told The Courier-Journal that Terrell learned last week that Saige was to be put up for adoption. Terrell told friends on Saturday she planned to take the boy and run away to New Mexico, Davis said.

"She loved her baby," Davis told the newspaper in a story published Wednesday. "She talked about how she was going to get her baby and everything back. She was buying clothes. She had a baby bed and a high chair and everything. ... I guess it made her snap."