The media has been covering a number of deaths in the Dominican Republic in recent weeks, most of which involve U.S. tourists who fall ill in the Caribbean nation due to circumstances that some find to be odd, which are under investigation.

The U.S. State Department announced that at least eight American tourists have died in the Dominican Republic in the past year, while dozens of others have gotten sick. About 2.7 million Americans visit the country every year and they have vacations that are relatively uneventful.

The aforementioned U.S. agency has confirmed that it is investigating the deaths of at least six American tourists in the country since the summer of 2018. The agency is not releasing additional details about the investigation.

“It’s definitely very strange,” Reynold A. Panettieri Jr., a physician at Rutgers who specializes in toxicology but is not directly a part of the investigations, said. “Healthy people don’t just die. And the couple dying at the same time certainly tips us off that something is very wrong.”

Some people fell ill after having drinks from their hotel minibar, which has led some to believe that these illnesses are the cause of tainted alcohol. Meanwhile, others believe that they may have gotten sick from pesticides, including a Colorado couple that felt ill after their visit to the country.

The CDC and FBI are investigating four deaths at several Grand Bahia Principe properties at the moment.