Transcript for Autopsies being performed on family of 4 found dead in Mexico

Next this Friday night, the family from Iowa on vacation in Mexico. The parents and two children discovered dead in the condo they had rented. Here's ABC's Matt Gutman. Reporter: Tonight, Mexican authorities are investigating the mysterious culprit that killed that vacationing family from Iowa. Mexican investigators say they found the sharps, Kevin, Amy, sterling and Adriana in the condominium they rented at this Seaside resort in tull lum. The sharps traveled from cresten Iowa for spring break. They let family know they got their safely, but then radio silence. That's what we thought was kind of unusual because last year they shared pictures about every day. Reporter: First, the family missed the meeting with friends and then they missed their flight home yesterday. Even though they had said they wanted to get back to watch their local basketball college team investigate division II tournament. We were hoping we would hear from them then, and when we didn't, we knew something was wrong. Reporter: The family said it's their understanding that the family went to sleep and never woke up. We'll know more when the autopsies are completed in Mexico.

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