NASSAU, Bahamas: After three Americans were found dead and another hospitalized on May 6, a faulty air conditioner leaking toxic coolant is believed responsible for the deaths of the tourists.

Following the deaths, tourist Chris Coucheron-Aamot, who is currently on holiday at the Sandals Emerald Bay resort in Exuma, posted on Facebook, "Three of our neighbors in the building right next to us died and a fourth was airlifted in critical condition early yesterday."

One of the dead Americans was identified as Vincent Chiarella of Birmingham, Alabama, whose wife, Donnis, was hospitalized. Both were in their mid-60s.

Most air conditioners use the chemical Freon as a coolant, which is a toxic gas that is tasteless and mostly odorless, which can prove fatal if inhaled over a prolonged period of time.

Local police are now investigating the deaths of the three American, two of whom complained of illness to hotel staff the evening before they died. It was since learned that two other guests, a couple staying at the same villa, suffered convulsions before their deaths.

"Our initial investigations revealed that the couple found in the second villa complained of illness the previous evening," a statement released by New Providence police said.

Hotel staff discovered the body of Chiarella shortly after 9 am on Friday in a villa next to the dead couple, the police added.

Chiarella's wife, Donnis, was airlifted to a hospital in the capital city Nassau, said Exuma MP and Minister of Tourism Chester Cooper.

She has since been airlifted to Kendall Regional Hospital in Florida, her son, Austin, told ABC News.

In a statement to DailyMail.com on May 6, a Sandals spokesperson said they were cooperating with the police investigation, but did not comment on inquiries regarding claims about the faulty air conditioner unit.

In an emailed statement, the representative wrote, "Nothing is more important to Sandals Resorts than the safety of our guests."