According to authorities, paramedics found Abby Lutz and John Heathco dead at Hotel Rancho Pescadero.
Two Americans were found dead in their luxury hotel room in Baja California Sur, Mexico, local police told ABC News.
Police and paramedics arrived at the Hotel Rancho Pescadero in El Pescadero around 9 p.m. Tuesday and found a man and a woman with no vital signs, police said.
The victims have been identified as John Heathco, 41, and Abby Lutz, 28, according to the Baja California Sur Attorney General's office. Lutz is from Newport Beach, California, the AG's office said. Local police initially said both victims were in their mid-30s.
Their cause of death was "intoxication by substance to be determined," the AG's office said in a statement Wednesday.
The man and woman had been dead for about 10 or 11 hours when they were found, the attorney general's office said. There were no signs of violence on their bodies, according to the AG's office.
"We can confirm the death of two U.S. citizens in Baja California Sur, Mexico on June 14. We offer our sincerest condolences to the families on their loss," a U.S. State Department spokesperson said Thursday. "We are closely monitoring local authorities' investigation into the cause of death. We stand ready to provide all appropriate consular assistance. Out of respect for the privacy of the families, we have nothing further to add at this time."
Hotel Rancho Pescadero is a luxury hotel and a Hyatt property.
"We are truly heartbroken by this terrible tragedy," Henar Gil, general manager of Rancho Pescadero, said in a statement. "Our hearts are with the impacted families and loved ones during this unimaginable loss. Local authorities are still actively investigating the situation, and the safety and security of our guests and colleagues remains a top priority, as always."
Hyatt didn't immediately respond to ABC News' request for comment.
ABC News' Will Gretsky and Shannon Crawford contributed to this report.