The three Americans who died last week at a Sandals resort in the Bahamas were from Tennessee and Florida, but their causes of death remain unknown, the island nation's police commissioner said Monday.Foul play is not suspected in Friday's deaths, Bahamian acting Prime Minister Chester Cooper has said.Forensic scientists have collected samples from the deceased, and a lab in Philadelphia is helping with toxicology examinations, Royal Bahamas Police Force Commissioner Paul Rolle said Monday. Scientists also collected samples from the rooms where the bodies were found to check for contaminants, he said.Officials declined to say whether any contaminants have been found in samples so far. Pathologists would provide an official report once the tests are complete, Rolle said.Michael Phillips, 68, and his wife Robbie Phillips, 65, from Tennessee were declared dead at the resort Friday, as was Vincent Paul Chiarella, 64, of Florida, who was found unresponsive in a separate room, police said.A fourth American — Chiarella's wife, Donnis Chiarella, 65 — was airlifted to a hospital in the Bahamian capital before being transferred to a Miami's Kendall Hospital, where her condition had been upgraded by Monday to fair from serious, said Jennifer Guerrieri, a spokesperson for Hospital Corporation of America's east Florida division.The three deaths at Sandals Emerald Bay resort on Great Exuma have been confirmed by Sandals spokeswoman Stacy Royal and the U.S. State Department."We are closely monitoring local authorities' investigation into the cause of death. We stand ready to provide all appropriate consular assistance," the State Department said in a news release. "Out of respect for the privacy of the families, we have nothing further to add at this time."Guests found unresponsive in resort villasResort staff alerted police shortly after 9 a.m. Friday that an unresponsive man had been found in a villa, police said. En route to the scene, police were told another man and woman were found unresponsive in another villa, the release said.Police found in the first villa a "Caucasian male lying on the ground unresponsive" with no signs of trauma. A doctor pronounced him dead, police said. The woman who was hospitalized was found with him, Rolle said Saturday.At the second villa, they found a second man "slumped against a wall in a bathroom unresponsive," and the woman was "found in a bedroom on a bed," the statement said."Both showed signs of convulsion," the release said. Neither showed signs of trauma. They were also pronounced dead by a doctor.The man and woman in the second villa had "complained of illness the previous evening" and received treatment at a local medical facility before returning to their room, police said.Cooper on Friday asked the nation's health and wellness minister to lead a delegation of health, environment and public works officials to the Exuma district."Nothing is more important to Sandals Resorts than the safety of our guests," the resort said in a statement, adding it is actively working to "support both the investigation as well as the guests' families in every way possible."Sandals cannot disclose further information "out of respect for the privacy of our guests," it said.