Heather Mack
Heather Mack, charged with the murder of her mother Sheila von Wiese Mack, in custody at a police station in Denpasar, Bali Getty

Indonesian police have charged an American couple with murder after the body of the woman's mother Sheila von Wiese-Mack was found stuffed in a suitcase at a luxury resort in Bali.

Heather Mack, 19, and her boyfriend, Tommy Schaefer, 21, both from Chicago, were arrested on Wednesday in Bali's Kuta area.

If found guilty of murder, the couple could be sentenced to death by firing squad under Article 340 of Indonesia's Criminal Code.

The body of Von Wiese-Mack was found inside the boot of a taxi parked in front of the St Regis resort in Nusa Dua on Tuesday. The 62-year-old academic, also from Chicago, was discovered half-naked with wounds to her head and appeared to have put up a fight, a local doctor confirmed.

The charges were based on witnesses and crime scene evidence, according to Bali deputy police chief Brigadier General Gusti Ngurah Raharja Subyakta.

Heather Mack Tommy Schaefer
Mack and Schaefer in Bali Instagram

Police said the couple hired the taxi and placed the suitcase in the boot, before fleeing the hotel via a back entrance. They were arrested after police found them sleeping at a hotel in Kuta on Wednesday morning.

Police chief for Bali's provincial capital of Denpasar, Colonel Djoko Hari Utomo, said the couple told investigators that Von Wiese-Mack was killed by robbers while they managed to escape. He added that their statement contradicted testimonies from the taxi driver and hotel staff.

During initial questioning on Wednesday, Mack acknowledged that her mother died, but refused to disclose how, according to Haposan Sihombing, an Indonesian lawyer assigned to the couple by police.

An autopsy was carried out at a hospital in Denpasar. The head of forensics, Ida Bagus Putu Alit, said there were signs of violence on the body indicating the victim had fought before she died.

"We found scars on both forearms and the broken left-hand fingernail. That indicated a resistance in a fight," Alit said, as reported by NBC News.

Authorities in Chicago examined records of 86 incidents in which police were called to a house in Oak Park, where Von Weise-Mack and her daughter lived. According to the Guardian, the pair had a tumultuous relationship.

The police calls started in 2004 and lasted until June 2013, according to Oak Park spokesman David Powers, who said the family moved out about a year ago. The majority of the calls were missing-person reports, and others included domestic problems and theft.