A police officer’s three-year-old daughter has died after being left unattended in a patrol car while her mum visited the home of a male colleague.1toddlerCheyenne Hyer was pronounced dead in hospital on Friday after being left in the vehicle, which had been running for four hours. Her mother Cassie Barker and fellow office Clark Ladner, who work for Hancock County Police Department in Mississippi, have both been suspended following the launch of an investigation.

Authorities are also looking into a prior incident involving Barker having her child taken away by officials. “We are looking into some possible previous allegations,” Hancock County Sheriff Ricky Adam said. “It is an active investigation. It hasn’t been determined which way we will go, but it doesn’t look good. We’ll see which way the evidence takes us.”

Glenn Grannon from the sheriff’s department said the cause of death appears to be overheating, even though the air conditioning was running in the patrol car when police found it Friday afternoon.

Hancock County Coroner Jim Faulk said Cheyenne’s body was sent to the state medical examiner’s office on Monday morning for an autopsy. The results are expected later this week.