A woman was arrested Thursday for allegedly murdering her 1-year-old daughter, dumping her body along a highway and telling authorities the child was kidnapped.

Stacey Barker, 24, has been under investigation since her toddler was found March 20 in tall grass a few blocks from a Los Angeles highway.

The woman initially reported being knocked out by someone while putting young Emma into her car and waking up to find the child missing. She later recanted the story and claimed the child died in an accident.

"Investigators discovered several inconsistencies in her story almost immediately," said Steve Whitmore, spokesman for the Los Angeles County sheriff's office. "As they continued to question her, her story began to change."

Whitmore said Barker had head injuries when authorities responded to her assault report. He said detectives are investigating whether they were self-inflicted.

Barker was detained for questioning after the child's body was discovered, but she was released into the custody of her parents several days later. She was booked Thursday on suspicion of murder and was being held on $1 million bond.

Barker's father told The Associated Press last month that Barker lived at home with her parents and younger brother who all took turns taking care of the family's first and only grandchild. Gary Barker said his wife worked at night so they wouldn't have to send Emma to day care, while his son watched Emma during the morning so other family members could rest.