Transcript for Suspect arrested in death of US woman in Costa Rica

Michael, we turn to the disappearance of that American woman killed in Costa Rica while vacationing. Her family confirming overnight her body was found near her airbnb and a suspect is now under arrest. Eva pilgrim is here with the latest. Good morning, Eva. Reporter: Good morning. It's been an agonizing wait for this family. The discovery now confirmed. Her family in Costa Rica saying they are devastated. This morning, the family of Carla Stefaniak, the American woman who went missing while vacationing in Costa Rica say they have confirmed the body found is that of 36-year-old Carla. It's too much for us. It's too much for us. Reporter: Based on her injuries she fought for her life. We are in complete -- Reporter: Arresting a 32-year-old security guard who lives next to the airbnb where Stefaniak was staying. He's been in Costa Rica for six months originally from Nicaragua. Second day. Reporter: Overnight investigators releasing these pictures from inside the airbnb. Authorities finding blood in Carla's room and her body in the mountainous area behind the home. Hi. Welcome for my birthday. Reporter: Stefaniak made a birthday trip to Costa Rica with her sister-in-law but when her sister-in-law flew back home Carla stayed an extra day on her own check nothing this airbnb, this picture of the room was the last she would send her family texting it's raining hard and the power went out. Super sketchy. Family says before her phone died she told them she was going to ask a guard for water. Her family has traveled down to Costa Rica searching for answers. They say they will always remember the joy Carla brought to their lives and how much she made them laugh. That's how I'm going to remember her. She's my baby. Your heart just breaks for that family. Authorities say that security guard became a suspect when his story didn't match up to what they found on security cameras but still a lot of questions for this family and so desperate for answers and want to know what happened. Sure. That's right. It is tough to see their hearts just being ripped out of their chest. We want to thank you.

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