The bodies of a Maryland couple who died on May 30 while vacationing in the Dominican Republic were returned to the United States on Tuesday, according to their family lawyer, Steven Bullock.

Edward Holmes, 63, and Cynthia Day, 49, were engaged and enjoying a five-day vacation at the Bahia Principe Hotel in La Romana; their bodies were found by hotel staff after they failed to check out of the hotel on the day they were to fly back to the United States.

EX-RED SOX SLUGGER DAVID ORTIZ LEAVES DOMINICAN REPUBLIC HOSPITAL FOR BOSTON AFTER BAR SHOOTING

(Facebook)

Autopsy results said the couple died from pulmonary edema, or excess fluid in the lungs, according to Dominican officials. A full toxicology report is pending.

Edward Holmes and Cynthia Day (Facebook)

A slew of recent deaths in the Dominican Republic have forced the Centers for Disease Control and Prevention and the FBI to team up with experts from several international agencies to assist Dominican authorities in investigating the resort. This, despite Dominican officials' insistence the deaths were due to natural causes.

Just five days before the bodies of Holmes and Day were found, another woman, vacationing with her husband at the same resort in an adjacent hotel also died of pulmonary edema.

Miranda Schaup-Werner, 41, a psychotherapist from Allentown, Pa., was celebrating her ninth wedding anniversary with her husband when she collapsed at the minibar at the Bahia Principe Bouganville hotel after having a drink.

Schaup-Werner's husband told Dominican authorities she "suffered from heart conditions in the past," the Bahia Principe resort group told Fox News in a statement.

Jay McDonald, a family spokesman for Daniel Werner, Miranda's husband, said his sister was diagnosed with inflammation around the heart 15 years ago, and sought treatment for it, but has since been medically cleared.

The family disagree with authorities' efforts to pin her death on a previous health condition.

“That was beyond coincidence,” McDonald said, responding to the Maryland couple's death. “They died five days after, and the cause was determined to be the same; this just puts this whole thing through the stratosphere – something is going on, and we want to know what it is.”

Also before the most recent deaths, a Delaware woman, Tammy Lawrence-Daley, has alleged that she was attacked by a man dressed in a hotel uniform at the Majestic Elegance resort in Punta Cana, where she was staying with her husband and two friends in January.

Lawrence-Daley, who posted to Facebook a graphic photo of her face, badly bruised and swollen from the alleged incident, said she was brutally beaten and thrown in a maintenance closet by her attacker, where she was found the next day by hotel staff.

This undated photo made available by Chris Daley shows his wife, Tammy Lawrence-Daley, after an alleged attack at a resort in the Dominican Republic in January. (Chris Daley via AP)

“I was strangled multiple times to unconsciousness. My lifeless body was drug down concrete stairs to an underground wastewater area. I was kicked in the head, I was beaten with a club. And then strangled again for the kill; at which time he disposed of my body into an area I refer to as the ‘hole.' I was unconscious multiple times during this savage attack, so I have no idea what else was done to me during that time,” she wrote.

A fourth U.S. citizen also died recently in the Dominican Republic, his family said on Sunday, telling Fox News they became suspicious about his death after learning about Schaup-Werner.

Robert Bell Wallace, 67, from California, was staying at the Hard Rock Hotel & Casino in Punta Cana to attend his stepson's wedding, almost a month before the other incidents occurred. On April 11, he had a scotch from the hotel's minibar and became suddenly ill.

"He started feeling very sick, he had blood in his urine and stool right afterward," his niece, Chloe Arnold told Fox News.

Robert Bell Wallace, 67, died in April after suddenly falling ill at a Dominican Republic resort.

Wallace was seen by a hotel doctor who then decided on April 13 that he needed to be hospitalized. He died the next day, and Dominican authorities have yet to give the family a cause of death, Arnold said.

The U.S. State Department issued a travel advisory for the Dominican Republic in April, urging those visiting there to “exercise increased caution … due to crime.”

“Violent crime, including armed robbery, homicide and sexual assault is a concern throughout the Dominican Republic,” the advisory said. “The wide availability of weapons, the use and trade of illicit drugs, and a weak criminal justice system contribute to the high level of criminality on the broader scale.”

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Most recently, famed Red Sox player David Ortiz was gunned down at a bar in the Dominican Republic on Sunday. The retired baseball player was in stable condition in intensive care at a Santo Domingo hospital, where doctors had to remove his gallbladder and part of his intestine. He was transported to a hospital in his hometown in Boston on Monday where he is still recovering.