Three Americans found dead at a rented apartment in Mexico City last month likely died of gas inhalation, police said Tuesday.

The city police department said security guards at the apartment building called after detecting an “intense smell of gas in an apartment” in an upscale neighborhood on the city’s west side. Three tourists were found unresponsive on Oct. 30 and port-mortem examinations suggest they died of carbon monoxide poisoning. 

A State Department spokesperson confirmed to USA TODAY the tourists were U.S. citizens who were visiting Mexico.

“We are closely monitoring local authorities’ investigation into the cause of death. We stand ready to provide all appropriate consular assistance,” the statement said. “Out of respect for the privacy of the families, we have nothing further to add at this time.”

Family members identified the tourists as Kandace Florence, 28, and New Orleans teacher Jordan Marshall, 28, according to WAVY, which first reported the deaths. Deanna Reddick, principal of KIPP Morial Middle School in New Orleans, confirmed the death of Courtez Hall, a 7th-grade history teacher, and said counselors would provide support to students and staff.

Relatives said the group rented an Airbnb in Mexico City to celebrate Day of the Dead last month.

On Oct. 30, Florence, who founded a candle business in 2020, told her boyfriend she was feeling sick and he contacted her Airbnb host to conduct a welfare check, WAVY reported. Authorities later found Florence, Marshall and Hall dead, according to the outlet.

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