The man was taken to a nearby hospital for treatment and was said to be in grave condition.
Director Alejandra Montalba of Santiago's Metropolitan Zoo told local media the park was crowded with visitors at the time of the incident.
The 20-year-old man broke into the enclosure, took off his clothes and jumped into the middle, horrifying other visitors who witnessed the attack. Zookeepers killed the two lions in order to save his life.
(Also watch: Drunk man jumps into a lion's enclosure in Hyderabad)
"The zoo has an established protocol because people's lives are very important to us," said Montalba, adding that there were no fast-acting tranquilizers available to stop the lions from mauling the man. She said she was "deeply affected" by the deaths of the two lions, a male and a female.
An apparent suicide note was found in the man's clothing, said Metropolitan Park director Mauricio Fabry. Witness reported he also made religious proclamations.
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