State public safety officials are planning to investigate Saturday's death of a Hawai'i inmate at a prison in Kentucky.

Relatives of Sarah Ah Mau, 43, allege that her pleas for medical attention were ignored by officials at the Otter Creek facility.

Frank Lopez, interim state director of public safety, said he was told by prison officials that Ah Mau's death resulted from a heart attack.

Lopez said state officials could fly to Kentucky this week to investigate Ah Mau's death.

Ah Mau's sister, Julie Frierson, said Ah Mau had been complaining of severe stomach pains for more than a month. A prison doctor called it "constipation" and gave her castor oil, her relatives said.

They said Ah Mau had told an inmate on Friday that she couldn't catch her breath. She was hospitalized, but died on Saturday, according to family members.

Ah Mau had been at the prison for 13 years. She was convicted in 1993 of murder for beating her 18-month-old son and denying him medical care that could have saved his life.

Ah Mau pleaded not guilty and would have been up for parole next summer.