Police are investigating the death Sunday of a 4-month-old Iroquois Point boy.

The medical examiner performed an autopsy of the infant yesterday, but the cause has not yet been released and will likely be deferred pending further studies, which may take six to eight weeks.

The boy’s father was watching him while his mother was napping, police said.

Police said the father went to wake him at about 6 p.m. and found the child unconscious. Cardipulmonary resuscitation was started, police said.

He was taken to the hospital, where he was pronounced dead, police said.