Transcript for New details on death of American family in Mexico

We have new details in that spri break tragedy that Kille an American family of four in Mexico. Mexican police have now revealed W they think that gas leak started and ABC's linsey Davis has the story. Reporter: This morning Mexican police believe all fou members of the sharp family saying at this upscale Mexican rert on spin break died from phyxiation after propane leaked from a rusted water heater. E bodies O Kevin and Amy sharp and their children, sterling and Adrianna were found on the top floor ofhis condominium near tulum, Mexico. The kids were on the floor watchingv and Kevin and Amy were on the bed watching TV and the TV was still goi apparent. Eporter: The main investigator spoke with "The des Ines register" and it occur the in the laundry room. It rusted in the humid climate andas purchased in 2012 and its warranty expired in 2017. The sharp family found the condo through the vacation home rentalcompany vrbohich has since remove the pperty from its site. Friends and family say they became concerned whether they didn't hear from theharps during their trip. Sterlingad sent a Snapchat out to a few of his friends showing his feet by the pool. And that was the last time anyone had heard from them. Their plans were to go to danville to watchhe swcc Spartans play in the playoffs. Reporr:ccording to the Ni exposure to very high concentrations of propane can cause death by suffocation. According to "The Des Moines register" a man said he stayed there several years ago and complained about the strong smell ofas from the water heater. He says that it was so B he shut it off andnly used the propane for a shower. That's what's most chilling about it that they didn't know. Even though they were awake and watching television is there apparently the smell wasn't that strong for them. Oh, gosh, okay, linsey, thank

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