BATON ROUGE - The mother of a five-month-old child whose death was ruled a homicide has been arrested for first-degree murder. 

On April 29, Baton Rouge Police Department arrested Shalyn Ewing, 30, for second-degree cruelty to a juvenile after the death of her five-month-old son Dominique Griffin. 

Griffin died from his injuries on May 3. His death was ruled a homicide. 

Thursday, officers announced that Ewing would be now facing a count of first-degree murder. 

Her arrest affidavit said that Ewing told police that she believed the child bumped his head against her wooden bed frame while he laid on the bed. She said he fussed but acted normal at first, but she brought him to the hospital a couple of hours later because she noticed his behavior was odd. She said she was alone with her son at home at the time he was injured and that she is his only guardian.

Hospital staff told police the events Ewing described didn't match the baby's injuries, according to the arrest affidavit.