Heather Mack, 19, and her boyfriend Tommy Schaefer, 21, both from Chicago, were arrested Wednesday in Bali's Kuta area, a day after the body of Sheila von Wiese-Mack was found inside the trunk of a taxi parked in front of the St. Regis Bali Resort.
The charges are based on witnesses and crime scene evidence, said Bali deputy police chief Brig. Gen. Gusti Ngurah Raharja Subyakta.
Police said the couple hired the taxi and placed the suitcase inside the trunk. They told the taxi driver that they were going to check out of the hotel and would return. After they didn't show up, hotel security guards who found blood spots on the suitcase suggested the driver take the taxi to the police station, where officers opened the suitcase and discovered the body.
The couple told investigators that von Wiese-Mack was killed by robbers while they managed to escape, according to the police chief for Bali's provincial capital of Denpasar, Col. Djoko Hari Utomo.
Utomo said that contradicted testimonies by the taxi driver and hotel employees.
Von Wiese-Mack, also from Chicago, and her daughter arrived at the St. Regis on Saturday, while Schaefer checked in on Monday, police said.
Security camera video showed that the victim had an argument with Schaefer on Monday in the hotel's lobby, police said.
Von Wiese-Mack's body was being autopsied at a hospital in Denpasar. Head of Forensics Ida Bagus Putu Alit said there were signs of violence on the body indicating that the victim fought before she died.
"We found scars on both forearms and the broken left-hand fingernail," Alit said following an external examination. "That indicated a resistance in a fight."
During initial questioning Wednesday, Mack acknowledged her mother died, but refused to disclose how, according to Haposan Sihombing, an Indonesian lawyer assigned by police to accompany the couple.
Sihombing said Mack and her mother arrived in Bali on Aug. 4, and stayed first at Simanyak Hotel before moving to the St. Regis on Aug. 9.
"When asked why they left the hotel and moved to Kuta, she did not respond," Sihombing said. "She even told police that three masked men entered their room, making her mother angry and that she asked them out, otherwise she would call the police."
Mack signed investigating documents and a letter of lawyer's assignment after Wednesday's questioning while Schaefer refused, saying he wanted to wait for his lawyer to arrive from America, Sihombing said.
"In principle, they did not respond to many questions," Sihombing said. "They were not cooperative."
Meanwhile, authorities in an upscale Chicago suburb, Oak Park, examined records of 86 incidents in which police were called to the house where von Wiese-Mack lived with her daughter. Friends have also started talking to local reporters, alleging that the mother-daughter relationship was sometimes contentious.
The calls started in 2004 and lasted through June 2013, according to Oak Park spokesman David Powers, who also said the family moved out about a year ago. The bulk of the calls were missing-person reports, and others included domestic problems and theft.
Powers didn't have details about the calls, but said none resulted in arrests. He added there were a number of emergency 911 calls made from the residence in which the caller hung up, and, as is standard procedure, the police department sent a squad car to investigate.
Von Wiese-Mack was the widow of highly regarded jazz and classical composer James L. Mack, who died in 2006 at age 76.
Von Wiese-Mack was a member of a century-old Chicago book club called the Caxton Club. She had varied interests including Asian literature and Wagnerian opera, according to a May 2013 profile of her in the club's publication, Caxtonian.
Associated Press writer Don Babwin in Chicago contributed to this report.
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