MADISON, Wis. -- Investigators said that they're trying to find out who is responsible for a baby girl's death last week in Madison.

The 4 1/2-month-old suffered what police are calling "non-accidental injuries."

The girl's parents called 911 from their south side home in the 2800 block of Perry Street early Friday morning. They said that girl wasn't breathing.

According to search warrants, investigators said that the injuries were inflicted over a period of time between five hours and 10 days prior to her death. The injuries including multiple, acute rib fractures, a bruise on her head, and evidence of fractures in both forearms.

One of the injuries ripped the tissue between her upper lip and gums and was likely the result of a baby bottle being forced into the child's mouth, according to the search warrant.

Emergency workers rushed the baby to Meriter Hospital, where she died.

Police said that they're interviewing the child's parents.

Stay tuned to WISC-TV and Channel 3000 for continuing coverage.