A Chicago man charged with murdering his girlfriend's mother told an Indonesian court Thursday he was angry after the victim threatened to kill his unborn baby, called him a racial slur and strangled him hard for about half a minute. Tommy Schaefer, 21, and Heather Mack, 19, are being tried separately by Denpasar District Court, where they are charged with premeditated murder for the death of Sheila von Wiese-Mack last August in Bali. They could face a firing squad if found guilty. The victim's bludgeoned body was found in a suitcase in the trunk of a taxi. Testifying at the trial of Mack, Schaefer told the court their relationship was not endorsed by his girlfriend's mother, and he went to Bali to decide how to tell her they were pregnant. Scroll down for video . Break down: Heather Mack, from Chicago, weeps in a courtroom as she witnesses her trial in Bali, Indonesia on Thursday, March 12, 2015. Mack, 19, charged with premeditated murder in the death of her mother . Trial: Mack told the court her boyfriend, Tommy Schaefer (right) killed her mother in anger after she threatened to kill their unborn baby . 'She attacked me': Schaeffer testified in court Thursday that the victim insulted him using a racial slur, described her daughter as a prostitute who liked a black man, and strangled him for 30 seconds . After meeting with Mack at the hotel, they discussed how to inform von Wiese-Mack that Mack was  pregnant and agreed to meet in the hotel room where Mack and her mother were staying. Speaking through an interpreter, Schaefer said Mack asked him to bring a metal fruit bowl, which he hid under his shirt as a 'precaution'. Asked by a judge why it was hidden, Schaefer answered that he was not sure whether he would use it or not to protect himself. According to Schaefer, he arrived in the room and found Mack weeping. He did not know why, but also saw that Mack's mother was screaming. 'She (von Wiese-Mack) was angry at me when she knew that Heather was pregnant,' Schaefer said, while trying to hold back tears. Mack, who was sitting beside her lawyer, sobbed at the testimony. He said that the victim insulted him using a racial slur and described her daughter as a prostitute who liked a black man. He said the situation got heated when von Wiese-Mack asked her daughter for an abortion or to kill the unborn baby. Schaefer said that led to a quarrel in which von Wiese-Mack strangled him hard for about 30 seconds. Heather Mack, 19, told an Indonesian court on Wednesday that her boyfriend Tommy Schaefer, 21, killed Shelia von Wiese-Mack (together-left) in anger after she threatened to kill their unborn baby . Heather Mack (left) and boyfriend Tommy Schaefer (right) arrive in court Thursday in Bali . Cuffed: Scaheffer says he was angry after victim threatened to kill his and Heather Mack's unborn baby . 'I was angry, I took the fruit bowl and hit her,' Schaefer said, in tears. He added that he did not remember how many times he hit the victim. After acknowledging she wasn't breathing, he tried to give her artificial respiration, while Mack, who had run in panic into the bathroom for about three minutes, came back and tried to revive her mother. He said he was trembling and scared and called 911 on his mobile phone before realizing that he was not in the United States. In her first questioning in court on Wednesday, Mack, who is eight months' pregnant, said Schaefer beat her mother with a metal soup bowl after von Wiese-Mack made the threat in an argument. 'The blow was not so hard ... and my mother was still resisting,' Mack said. 'I asked Tommy to stop and then I ran into the bathroom.' Von Wiese-Mack's bludgeoned body was folded in half and stuffed into a suitcase with bloody sheets. The suitcase was later found in a taxi at the posh St. Regis Hotel in August. Deceased: Shelia von Wiese-Mack's late husband, and her daughter's father, was composer James Mack . Pregnant: The couple, seen here together in an Instagram picture from last year, are expecting a child . Trial: According to the indictment, Schaefer battered von Wiese-Mack with the metal bowl following an argument over the hotel bill . Heather Mack (left) and her boyfriend Tommy Schaefer, from Chicago, Illinois, sit in a cell before a trial in Bali . Mack said when she left the bathroom, she found Schaefer on the bed trying to give her artificial respiration. 'Tommy said my mother was not breathing,' she said. Mack said she also tried to revive her but it didn't work. She said they panicked and thought about either calling the police or taking the body in a suitcase to the U.S. Consulate. She did not explain why they did not do either one. 'We panicked and didn't know what to do,' she said. Mack answered 'no' when the judge asked whether she wished her mother dead. 'Troubled': Mack has previously been described as 'troubled' and 'violent' by friends of her family . Heather Mack and Tommy Schaefer, accused of murdering Sheila von Wiese-Mack, were pictured in handcuffs as they arrived for their latest court appearance in Bali on Wednesday . Heavily pregnant Mack (right), 19, and Tommy Schaefer (second from left), 21, sit in the court room in front of what is believed to be the suitcase they are accused of using to hide the body of von Wiese-Mack . Mack and Schaefer arrived in court, handcuffed together and wearing matching orange waistcoats. The pair sat in court in front of evidence believed to be a suitcase they are accused of using to hide the body of Mack's 62-year-old mother. According to the indictment, Schaefer battered von Wiese-Mack with a fruit bowl handle in her room following an argument over the hotel bill. It says Mack helped stuff her mother's body into the suitcase by sitting on it to enable Schaefer to close it. The indictment says they then placed the suitcase in the trunk of a taxi and told the driver they were going to check out of the hotel and would return, but never did. Hotel security guards are said to have seen blood spots on the grey suitcase and the taxi driver went to the police, who then made the gruesome discovery. The pair were wearing matching orange waistcoats as they arrived for their latest court appearance on Wednesday . Sheila Von Wiese-Mack's badly beaten body was found in a suitcase in the trunk of a taxi at the hotel . The first witness to testify at Schaefer's trial, a bellboy named Arifin, said he saw the couple taking a suitcase on a baggage cart toward the lobby on August 12. He said during proceedings in February that he asked them about the hotel bill, which according to a receptionist hadn't been paid, but Mack refused to respond. 'They asked me to call a taxi, but they refused when I offered to help put the bag into the taxi,' he said. 'They argued that the contents were fragile, and refused to be assisted.' Arifin, who uses a single name, said he heard about the murder later from police. The second witness was I Putu Adi Marta, a technician who examined the hotel's security videos on August 12. 'I was asked to check because a couple, a man and a woman, were said to have escaped without paying the hotel bill,' he said. Marta said the video recordings showed that Schaefer and Mack used the emergency stairs several times to go between the third and sixth floors. Mack and her mother were staying in a room on the third floor, while Schaefer was staying on the sixth floor. 'The man walked up and down from the third to the sixth floor, changed his shirt once and brought a white cloth,' he said. 'They also were shown bringing a large package from the third to the sixth floor.' The pair (pictured together in a cell), from Chicago, Illinois, are being tried separately by the Denpasar District Court . A police officer also testified that he was among five police who arrested the couple on August 13 at the Bali Wisata Hotel in the Kuta area, about 10 kilometers (6 miles) from the St. Regis hotel. 'First they refused to be taken without being accompanied by lawyers from their government,' I Made Ariyana said. He said they also refused to talk or be photographed at the Kuta police station. Schaefer did not object to any of the testimony. Prosecutors said before visiting Bali, Mack had suggested that Schaefer hire someone for $50,000 to kill her mother, who objected to their relationship. Mack and her mother had arrived first in Bali and were staying in a room on the third floor of the hotel, while Schaefer arrived later and was staying on the sixth floor. Schaefer and Mack listen to proceedings as they sit in the court room in Bali, Indonesia .
Heather Mack, 19, and boyfriend Tommy Schaefer, 21, accused of killing her socialite mother Sheila von Wiese-Mack in Bali in August . Mack, now eight months pregnant, broke down in tears at trial Thursday . Schaefer testified the victim was against their relationship, called him a racial slur and her daughter a prostitute who liked a black man . He hit her with a metal fruit bowl out of anger, Schaefer said . Mack told the court Wednesday Schaefer killed her mom  after she threatened to kill their unborn baby . Von Wiese-Mack's bludgeoned body was found wrapped in bloody sheets in a suitcase in the trunk of a taxi at the hotel . Couple put suitcase in trunk, told driver they were checking out, then never returned to the car .