The police in Samoa are investigating a suspected infanticide after a newborn baby was buried by a family who did not inform health authorities.

Police said a 20-year-old woman gave birth to the baby at her home in a village to the west of Apia last Thursday.

The woman's mother - who helped deliver the baby - is alleged to have then instructed another family member to dig a hole for burial.

The police would not say if the baby was alive when it was born.

Meanwhile, police are investigating another alleged infanticide on Savaii after the body of a newborn was found at Salelologa market this week.