An extensive FBI toxicology report ruled out tainted alcohol as the cause of death of three American tourists who died in the same Dominican Republic resort in May, The Huffington Post reported on Saturday.

The tests were conducted for Nathaniel Holmes, 63, Cynthia Day, 49, and Miranda Schaup-Werner, 41. Holmes and Day were an engaged couple from Maryland who were found unresponsive in their room on May 30, the day they were to check out of the Grand Bahia Principe Hotel La Romana at the Playa Nueva Romana resort, as CrimeOnline previously reported. Schaup-Werner died five days earlier at the Luxury Bahia Principe Bouganville in the same resort, HuffPo said.

Dominican authorities said that Holmes and Day both had  internal bleeding and died from respiratory failure and pulmonary edema caused by excess fluid in their lungs. Schaup-Werner died of pulmonary edema, internal hemorrhaging and an enlarged heart, authorities said, according to HuffPo.

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Several American tourists died in the Dominican Republic under mysterious circumstances this summer, prompting other visitors who became ill or family members of others who died to question what may have happened to them. Some of the victims drank alcohol not long before they died, which launched questions about whether the liquor they drank was contaminated.

The FBI told Dominican authorities in mid-September their tests had eliminated tainted alcohol as a cause of death, but the law enforcement agency said it had not completed its investigation.

“In the interest of providing as thorough an investigation as possible in this challenging case, the FBI is testing for two additional toxins and will provide Dominican authorities with results when tests are complete,” FBI officials said, according to BuzzFeed News.

BuzzFeed reported that the State Department has not seen a rise in the number of deaths of American tourists in the Caribbean nation, however. Between January and June this year, the State Department said 10 Americans have died there. In 2018, the total number for the year was 13, and in 2017, it was 17.

See more about mysterious deaths and illnesses in the the Dominican Republic from CrimeOnline.

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