Police in the Bahamas are investigating in the wake of the deaths of three U.S. travellers at Sandals Emerald Bay on May 6.

A fourth traveller is in hospital.

Foul play is not suspected and the cause of death is still unknown, said The Bahamas’ Acting Prime Minister Chester Cooper.

Health Minister Dr. Michael Darville said environmental health scientists, physicians and others were being investigating, to ensure there was not a public health hazard.

“We feel that what we are seeing is an isolated case associated in a particular area,” he said, adding that investigators are doing toxicology and blood tests to help determine the cause of the illness.

Earlier a representative for Sandals confirmed the deaths, saying the company is “actively working to support both the investigation as well as the guests’ families in every way possible during this difficult time.”

With file from The Associated Press and Travelweek