BOGALUSA, La. -- A woman whose 6-week-old baby died after being burned, beaten and drugged says she thinks the motive was revenge, a Bogalusa newspaper reported Friday.

Baby Diana Nelson

Amy Leighanne Thomas, 22, has been arrested in the case.

The child's mother, Lindsey Daigle, 19, told The Daily News that she had told another woman that Thomas had taken something from her work locker. Daigle said she believes Thomas harmed the baby after finding out that Daigle had talked about the alleged theft.

Daigle does not work at the store in question, and did not tell the newspaper how she learned about the alleged theft.

Thomas denied the allegations in an interview with the newspaper. She said she took Diana Nelson to her home and bathed her, but did nothing to hurt the baby.

Sgt. Darrell Darden, spokesman for the Bogalusa Police Department, was out of the office and could not be reached immediately for comment.

The newspaper interviewed both women Tuesday, a day before Thomas was arrested. Police asked the newspaper at the time to delay publication of the report because it might jeopardize the investigation, publisher and editor John Walker said.

Thomas was booked Wednesday with second-degree cruelty to a juvenile; after the baby died on Thursday, police said the charge would be increased to first-degree murder.

Investigators have said the infant was beaten on the head, singed with a curling iron and drugged. Police also have said that Thomas confessed on Wednesday.