An Indonesian court found a young U.S. couple guilty on Tuesday of murdering the woman's mother and stuffing her battered body into a suitcase on the resort island of Bali.
Heather Mack and Tommy Schaefer, both from the Chicago area, were arrested last August after staff at a luxury hotel discovered the body of Mack's mother, Sheila von Wiese-Mack, in an abandoned suitcase in a taxi.
Schaefer was sentenced to 18 years in prison for premeditated murder immediately after the verdict was delivered by a panel of three judges, and Mack to 10 years for being an accessory to murder.
The pair were tried separately in Denpasar District Court and it was not immediately clear if they would appeal.
Schaefer, 21, who had said in court he had killed Wiese-Mack in self-defence after she attacked him in anger because she objected to the couple's relationship, apologised to the family of the victim.
"Although I do take full responsibility for my actions, I am not a murderer," he told Reuters after hearing the verdict.
Prosecutors had called for a 15-year sentence for Mack, 19, because she faced a lesser charge and because she recently gave birth to a baby girl.
"10 years is better than the 15 years sought by the prosecution, so (we're) happy," said Ni Ketut Novi Sri Wirani, Mack's lawyer.
Presiding Judge Made Suweda spent more than an hour reading out the grisly details of the killing before delivering the verdicts.
"In my decision I have made a special judgment because Heather has a baby who needs a mother," said the judge. "For Tommy, I call the crime sadistic."
Bali police, assisted by the U.S. Federal Bureau of Investigation, conducted a four-month investigation into the killing, including a re-enactment with the defendants at the five-star St Regis Bali Resort where the body was found with bruises on her arms and broken fingers.
Other evidence submitted to prosecutors included CCTV footage showing the couple speaking to a taxi driver after dropping the bloodied suitcase along with other luggage outside the hotel.
Mack and her mother had a troubled relationship and von Wiese-Mack had frequently reported that her daughter punched and bit her, according to police reports cited by Chicago media.
Von Wiese-Mack's husband and Heather's father, classical music composer James Mack, died in 2006.