“I think there’s probably some kind of negligence somewhere,” Jason Allen said on Thursday.

But on Friday, Francisco Javier García, the tourism minister of the Dominican Republic, said the deaths of eight Americans in the country were not part of a mysterious crop of fatalities, The Associated Press reported. Mr. García said that autopsies had revealed that five tourists had died of natural causes, and that Dominican officials believed the three others currently undergoing further toxicological testing would reveal the same cause of death. “We want the truth to prevail,” Mr. García said. “There is nothing to hide here.”

News of Mr. Allen’s death came just days after Leyla Cox, 53, from Staten Island, died in her hotel room at Excellence Resorts in Punta Cana. Other deaths, which appeared to be related to cardiac issues, included: Yvette Monique Sport, 51, of Glenside, Pa., at a Bahia Príncipe resort in June 2018; Mark Hurlbut, 62, of Grand Prairie, Tex., in June 2018; David Harrison, 45, of Maryland, at the Hard Rock Hotel & Casino Punta Cana in July 2018; Robert Wallace, 67, of California, at the Hard Rock Hotel & Casino Punta Cana in April of this year; Miranda Schaup-Werner, 41, of Allentown, Pa., at the Luxury Bahia Príncipe Bouganville, on May 25; and Nathaniel Edward Holmes, 63, and Cynthia Ann Day, 49, of Prince George’s County, Md., at the Grand Bahia Príncipe La Romana on May 30.

The Hard Rock Hotel & Casino in Punta Cana said in a statement on Friday that it had removed minibars from all guest rooms. “All of the alcohol on property will continue to be brand name and sourced from the U.S., with the exception of a Dominican Republic specialty, Mama Juana, and local beer, Presidente, that we carry to support our community,” the statement read.

The F.B.I. is in the Dominican Republic investigating the deaths.

“At the request of Dominican authorities, the F.B.I. continues to assist with the ongoing local investigation, to include support with toxicology as well as the arrival of a small team of F.B.I. personnel in the Dominican Republic,” a State Department official told The Times on Friday evening.

On the State Department website, the Dominican Republic has a “level 2” travel warning (on a scale of one to four) that encourages travelers to “exercise increased caution” if traveling to the island. The warning was last updated in April.