Transcript for Father of US tourist killed in Costa Rica: 'We are incomplete'

And next this evening, from Costa Rica, a heartbreaking confirmation for the family of that American woman who disappeared on the last day of her vacation. Her father now identifying the body found near the airbnb where his daughter was staying for her birthday. And tonight, investigators say it appears she did die after a violent struggle. Here's ABC's Eva pilgrim. We're incomplete. Reporter: Tonight, the father of Carla Stefaniak is struggling to make sense of the brutal murder of his beloved daughter. It's too much for us. That's too much for us. Reporter: Authorities revealing new details about the murder of the 36-year-old who came to Costa Rica on vacation Second day. The hot springs. Reporter: They think Stefaniak fought for her life. She was stabbed, her neck broken inside this airbnb. Police arresting 32-year-old bismark Martinez, a security guard who lived next door. Investigators suspect the crime was sexually motivated. How they welcome me for my birthday! Reporter: Stefaniak stayed an extra day on her own, checking into this airbnb. This picture of the room, the last she would send her family. Texting, "It's raining hard and the power went out. Super sketchy." David, the lawyer for that airbnb says the complex is closed and the owners are cooperating with the investigation. David? Eva pilgrim tonight. Thank you, Eva.

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