Charges against a teenage father who allegedly bashed his baby son at a West Australian hospital may be upgraded following the infant's death.
Police allege the month-old baby was attacked at Bunbury Regional Hospital on February 15.
Left with critical head injuries, the premature infant died in Princess Margaret Hospital on Monday.
His 15-year-old father, a ward of state, was charged last week with aggravated grievous bodily harm.
On Tuesday, police said charges may be upgraded pending the results of a post mortem.
"Major Crime Squad officers will continue their inquiries into the matter," a police spokeswoman said.
Department for Child Protection director general Terry Murphy said the WA coroner and ombudsman would investigate the cause of death, and review the circumstances and events that led to the tragedy.
The 15-year-old is due to appear in Perth Children's Court on Friday.