CLINTON, Maine — The death last month of a 3-month-old girl who was staying with a baby sitter is being investigated as a homicide, Maine Department of Public Safety spokesman Stephen McCausland said Wednesday.

Maine State Police are investigating the case in conjunction with the state medical examiner’s office, he said. Brooklyn Foss-Greenaway died July 8 while under the care of a baby sitter in Fairfield, according to The Associated Press.

No charges have been filed, the AP said.

“We’ve been investigating the death since July. Now we’re investigating it as a homicide,” said McCausland. “Other details as to where we are in the investigation, we’re not going to talk about publicly.”

The death of any child under age 3 automatically triggers an investigation.

The baby’s parents live in Clinton and had arranged for the child to spend the night at the baby sitter’s Fairfield home, according to the AP.

Emergency officials arrived just six minutes after receiving a call in the early morning hours that the child was unresponsive and not breathing.