The department says "the results of the additional, extensive toxicology testing completed to date have been consistent with the findings of local authorities." The department says that families have been informed of the results.
The first deaths to make headlines were in May, when a couple seemingly died at the same time in the same hotel room.
The Dominican Republic's tourism minister said in June that the deaths were not part of any mysterious series of fatalities but were a statistically normal phenomenon being lumped together by the U.S. media.
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