A 1-month-old infant died Monday evening and his twin brother was taken from their home by Child Protective Services after Modesto police responded to a call of a child not breathing.

Medical personnel were called to the family’s home in the 1200 block of Main Street in the Shackelford neighborhood at 5:30 p.m., said Modesto police Sgt. Rick Applegate.

An autopsy was performed Tuesday. The cause of death, while it appears to have been medical, could not be determined for sure until the pathologist receives toxicology results, Applegate said.

Police and Child Protective Services went to the home, which was a trailer in the back yard of a house on Main Street, Applegate said. Living conditions there were determined to be unsuitable for children and the twin brother was taken by CPS.

Applegate did not know how many adults lived in the trailer or who had custody of the boys but said no one was arrested.