A fourth American tourist is reported to have died after a sudden illness at a luxury resort in the Dominican Republic, a month after three other tourists died in their rooms in separate incidents.

On Sunday Robert Bell Wallace was struck down by a sudden illness after drinking from the hotel minibar in his room at the Hard Rock Hotel & Casino, reported Fox News.

The 67-year-old from California was in the country to attend his stepson's wedding.

Arnold, the victim's niece, said Wallace had been in good health before the incident and had been skiing in Lake Tahoe just a month before his death.

Advertisement
Mr Wallace had been on a skiing holiday with his wife, just a month before his sudden illness and death. Photo / Supplied
Mr Wallace had been on a skiing holiday with his wife, just a month before his sudden illness and death. Photo / Supplied

The family were particularly concerned after learning of the other mysterious deaths in Dominican Republic hotels.

Miranda Schaup-Werner of Pennsylvania died in similar circumstances after staying at another hotel, the Bahia Principe la Romana.

Schaup-Werner reportedly collapsed and did not recover after drinking from her hotel minibar, according to reports. The 41-year-old psychotherapists had checked into the luxury hotel with her husband to celebrate their wedding anniversary. She died on March 25, just four weeks before yet another incident was reported.

Miranda Schaup-Werner died while celebrating her anniversary in the Dominican Republic. Photo / Twitter.com
Miranda Schaup-Werner died while celebrating her anniversary in the Dominican Republic. Photo / Twitter.com

On May 30, the bodies of two other guests were discovered in their room at the Bahia Principe Hotel buy staff. Mr Holmes and Ms Day from Maryland reportedly died of respiratory failure and pulmonary edema.

Regional Institute of Forensic Sciences INACIF is conducting further toxicology and histopathological tests.

Edward Holmes and Cynthia Day were found dead in their room by hotel staff. Photo / Facebook.com
Edward Holmes and Cynthia Day were found dead in their room by hotel staff. Photo / Facebook.com

Arnold told Fox News that the incident was a shock for the family and left them with "so many questions."

"He and his wife arrived there at around midnight on April 10. On April 11 he had scotch from the minibar. He started feeling very sick, he had blood in his urine and stool right afterwards."

Wallace was referred to hospital on April 13, and died on April 14.

Advertisement
Roughly half of the Dominican Republic's 5 million annual tourists come from the United States. Photo / Getty Images
Roughly half of the Dominican Republic's 5 million annual tourists come from the United States. Photo / Getty Images

While the Dominican authorities are still waiting for further toxicology results, the deaths are being treated as isolated incidents. However, some of the victims' families have hired lawyers and intend to undertake additional autopsies in the United States.

The Grand Bahia and Dominican authorities have not yet responded to questions regarding a possible connection to the deaths.

A number of American agencies including the Centres for Disease Control and Prevention and even the FBI have confirmed that they were conducting investigations on the properties at Bahia Principe.

Roughly half of the Dominican Republic's 5million annual visitors come from the USA.