BALI, Indonesia (AP) — Indonesian police say an American man has confessed that he killed his girlfriend’s mother in a Bali hotel, and the girlfriend has acknowledged helping him stuff the body into a suitcase.

Heather Mack, 19, and her boyfriend Tommy Schaefer, 21, both from Chicago, were arrested in Bali on Aug. 13, a day after the body of Sheila von Wiese-Mack was found in a suitcase inside the trunk of a taxi at the St. Regis Bali Resort.

Police chief Col. Djoko Heru Utomo said Friday that Schaefer confessed during an interrogation on Monday and that Mack acknowledged her role in separate questioning later this week.

Attempts to reach their Indonesian lawyers were not immediately successful.

Utomo said Schaefer confessed that he killed the woman after an argument.

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