Officials have launched an investigation after three American tourists were discovered dead at a Bahamas resort on Friday.

Sandals confirmed that the guests were staying at the Sandals Emerald Bay in Exuma.

A man was discovered unresponsive in a villa by resort staff shortly after 9 a.m. Friday, and another man and woman were discovered unresponsive in another villa while police were en route, police said.

According to authorities, the man was discovered lying on the ground in the first villa with no signs of trauma. The man was discovered “slumped against a wall in a bathroom” in the second villa, and the woman was discovered on a bed, according to the Royal Bahamas Police Force. “Both individuals displayed signs of convulsion,” according to police. There were no signs of trauma on either body.

Dr. Michael Darville, Bahamas Minister of Health and Wellness, told ABC News that some hotel guests went to a clinic Thursday with nausea and vomiting, were treated, and then left. Three were later discovered dead, while a fourth, a woman, was flown to a hospital in New Providence and is in stable condition, according to him.

On Friday, police said they were working to confirm the identities of the deceased.

Vincent Chiarella of Birmingham, Alabama, was one of the victims, according to his son, Austin Chiarella.

Vincent Chiarella, in his mid-60s, was in the Bahamas with his wife, Donnis Chiarella, for their anniversary, according to their son. Donnis Chiarella, also in her mid-60s, was the fourth victim to survive, according to Austin Chiarella. He said she is being airlifted to the Kendall Regional facility in Florida and will arrive late Saturday afternoon.

Austin Chiarella said he received a call from the US Embassy with the news Friday night and spoke with his mother Saturday morning.

“She awoke to find my father laying on the floor, and she couldn’t move,” he explained. “Her legs and arms were swollen, she couldn’t move, and she screamed for someone to come in.”

Donnis Chiarella told her son that she had become ill on Thursday but “thought she was fine” after being released from the clinic. “I’m just heartbroken right now,” Austin Chiarella explained. “My father meant everything to me.”

According to Darville, environmental health scientists, physicians, and others are investigating to ensure there was no public health risk.

“There is no potential risk to any of the residents on Exuma, including residents at the resort or any other resort on the island,” he said.

According to Acting Prime Minister Chester Cooper, the cause of death is unknown, but no foul play is suspected.

Sandals stated that it is “actively working to support both the investigation and the guests’ families in any way that we can.”

“A health emergency was initially reported and following our protocols we immediately alerted emergency medical professionals and relevant local authorities,” the company said in a statement. “Out of respect for the privacy of our guests, we cannot disclose further information at this time.”

Cooper asked the nation’s health and wellness minister to lead a delegation of health, environment and public works officials to the Exuma district on Friday.

“The public will be kept abreast of information as soon as it becomes available,” Cooper, who also is the Bahamas’ tourism minister, said. “We offer our thoughts and prayers to the families affected.”