Story highlights A Colombian official confirms the plane had no fuel

An air traffic controller says she's received threats since the crash

(CNN) The air traffic controller who last spoke with the pilot of LaMia Flight 2933 before the plane crashed told her colleagues she did everything she could to keep the flight's occupants alive.

"I can affirm with absolute certainty that, for my part, I did what was humanly possible and technically required to preserve the lives of these users of air transport," Yaneth Molina wrote in an email to fellow air traffic controllers. "Unfortunately, my efforts were unfruitful, because of the reasons that you all know."

Molina's email was published Thursday by CNN affiliate Cablenoticias , and Carlos Llanos, president of the Colombian Association of Air Traffic Controllers, confirmed its authenticity to CNN.

The plane crashed Monday night near Medellin, Colombia, killing more than 70 people, including members of the Brazilian soccer team Chapecoense

Colombian authorities say they've confirmed the plane had no fuel when it crashed.

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