Disturbing details emerge in case of former Marine and his girlfriend found dead in Belize

The mysterious death of an Atlanta man and his girlfriend has taken a disturbing turn -- police say they believe the couple was murdered.

Investigators revealed shocking new details in the death of Drew DeVoursney, 36, and Francesca Matus, 52, in Belize.

According to WSBTV, their bodies were found in a sugar cane field with duct tape around their wrists.

Authorities certified that they died from strangulation after a postmortem exam on Tuesday. They did not mention any possible suspects.

The couple was last seen leaving a bar in Belize on April 25.

DeVoursney's mother told WSB-TV that he had lived in Belize since December. He had been dating Matus for just a few months.

Matus was set to return home to Canada on Wednesday, but when her friend showed up to take her to the airport, he noticed that her house was locked and her car was gone.

DeVoursney's mother also mentioned that her son was planning to return to Atlanta on Friday.

She said her son was having trouble finding work in the country.

WSBTV reports that authorities in Belize are working with the U.S. Embassy and Canadian Consulate as the investigation continues.