ARLINGTON — On Monday, Nov. 28, at approximately 3 p.m., Snohomish County Sheriff’s Office deputies responded to the 14000 block of 95th Avenue NE in Arlington to assist fire personnel with an unresponsive male infant.

Upon their arrival, the fire personnel had already begun CPR on the four-month-old infant.

Preliminary information indicates the infant was put down to sleep earlier by his mother. When she checked on the infant later, he was unresponsive and not breathing.

The infant was transported to Cascade Valley Hospital by medics, and was pronounced dead at the hospital.

Detectives from the Sheriff’s Office Major Crimes Unit responded to the location and have taken over the investigation.