Police have increased security around Papua New Guinea's acting prime minister for fear of a traditional revenge attack after his 21-year-old son was accused of murdering a woman at the family home, an official said Friday.

A cordon was thrown around Acting Prime Minister Sam Abal's house in the capital, Port Moresby, where police allege his son, Theo Abal, slashed the throat of a 29-year-old hostess he met in a bar Monday, police spokesman Dominic Kakas said.

The cultural practice of payback has a long tradition in the South Pacific's most populous island nation, with a murder victim's clan often taking out revenge on the killer or his family.

"It does happen, and we're not saying it won't happen, so we've taken all precautions to protect the acting prime minister," Kakas said.

"It usually is an eye for an eye and a tooth for a tooth, but we try to make peace between tribes, and in a lot of instances, common sense prevails," he said.

Kakas said the youngest of Sam Abal's two sons, who was adopted, will be charged with willful murder. But first, relatives of the woman, who came from a province more than 60 miles (100 kilometers) northwest of Port Moresby, must formally identify her body, he said. The woman went by the name Theresa, but her full name has not been released.

According to Kakas, "the suspect confessed in his statement to having killed the lady."

Kakas declined to comment on the motive.

Theo Abal, who is unemployed and was living with his father in the house, was arrested at a Port Moresby hotel Tuesday and remained in police custody Friday. He could face the death penalty if convicted.

A guard at the house told police he saw Abal and the woman arrive home in the early hours of Monday and head for a garden on the premises. Police said that the guard later heard the woman scream and that Abal confessed to killing her.

Kakas said a kitchen knife found near her body was the suspected weapon.

Sam Abal said he personally reported the "alleged murder" to Police Commissioner Tony Wagambie on Monday.

He made no comment on his son's alleged confession, but pledged to cooperate fully. He said in a statement Tuesday that if any of his relatives were involved, "they will face the full brunt of the law and will not be treated differently from anyone else."

Papua New Guinea has had the death penalty for only a few years and has yet to carry out an execution, though a handful of convicted killers have been sentenced to death, Kakas said.

According to Wagambie, the acting prime minister was away from the house and was alerted to the death by the security guard, who found the woman's body in a banana garden.

Sam Abal is standing in for Prime Minister Michael Somare, who stepped down in December because of ill health and to clear his name before a tribunal that is investigating allegations that he failed to disclose his full income.