MEXICO CITY (CBS NEWS/AP) – Mexican authorities said Saturday the American family of four who were found dead in a tourist city died from inhalation of toxic gases.

The bodies of Kevin, Amy, Sterling and Adrianna Sharp were discovered Friday inside a condominium in Akumal, in the Mexican state of Quintana Roo.

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The Sharp family. (Ashli Peterson/Facebook)

The prosecutors’ office in the Quintana Roo said that “the cause of death was asphyxiation from inhaling toxic gases.” It said the type of gas hadn’t yet been determined, but added that “any violent act or suicide has been discounted.”

Photos released by the office showed investigators in anti-contamination suits and firefighters with air tanks examining gas connections to a stove in the condo in Tulum.

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The office said investigators “carried out a physical investigation of the gas connections in the room,” and the civil defense office of Tulum would issue a technical report on the findings.

The state Attorney General’s office said that forensic doctors determined the family was dead for approximately 36 to 48 hours before they were found. The type of gas or where it came from was not specified.

The family had not been heard from since they left for Mexico on a trip on March 15. According to CBS Des Moines affiliate KCCI-TV, according to family members’ social media posts, Kevin, 41, Amy, 38, Sterling, 12, and Adrianna Sharp, 7, were expected to arrive in St. Louis on Wednesday to attend a basketball game in Danville, Illinois.

On Friday, Mexican officials said there was no sign of foul play in the deaths.

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