(CBS/AP) COLUMBIA, S.C. - Authorities have called off the search for a toddler who has been missing since Thanksgiving, and whose mother is in jail for allegedly lying to police about the boy's whereabouts.
Federal, state and local police officers used cadaver dogs to scour an eight-mile radius for more than four hours Thursday, looking for 18-month-old Amir Jennings, but found no evidence of the boy.
The boy's mother, 22-year-old Zinah Jennings, has been in jail since late December. Her mother, Jocelyn Jennings Nelson, reported Amir missing early in December when she said she received evasive answers from Zinah about Amir. Family members say they last saw the little boy around Thanksgiving.
On Christmas Eve, Zinah Jennings encountered police after a car wreck. At first she said she didn't have any children, then told officers her son was with relatives and friends in cities from Atlanta to Charlotte, N.C.
Investigators say they chased down Jennings' stories but finally arrested her after they ran into dead ends. State police are analyzing stains on blankets and clothes removed from Jennings' car to see if they are blood.
According to Jennings' attorney, Hemphill Pride II, Jennings should be released from jail because she is pregnant, suffering from mental illness and needs medical treatment.
In his motion filed Tuesday, Pride cites a doctor who has examined Jennings and says she "lacks sufficient insight or capacity to make responsible decisions" about her treatment and needed to be committed to the hospital.
Jennings' half sister told police she suffered from "schizophrenic tendencies" that had not been diagnosed and Pride said she has been told to take Risperdal, which is used to treat symptoms of schizophrenia.
"She's incapacitated at this time, so she's not in a position to cooperate," said Pride. "The medicine that she's on right now, she's quite frankly, zonked."
Shortly before her son disappeared, Jennings was arrested in Georgia on prostitution and drug charges.
Nelson has said her daughter had been depressed since the birth of her son, struggling in classes at a community college and looking for a job.
A hearing in the case is scheduled for Monday, Jan. 30.