A kayaker is speaking out after he briefly found himself inside the mouth of a whale.

Adrián Simancas was with his dad, Dell, in the Strait of Magellan, a tourist attraction in Chilean Patagonia, on Saturday, Feb. 8, when he suddenly found himself inside the mouth of the humpback whale, according to the Associated Press.

Footage of the encounter, captured by Dell, showed the kayaker quickly getting scooped up into the massive animal’s mouth and disappearing for a few seconds before resurfacing a few yards away.

Speaking with the AP, Adrián said he feared for his life while inside the whale.

“I thought I was dead,” he explained in Spanish. “I thought it had eaten me, that it had swallowed me.”

“When I turned around, I felt on my face like a slimy texture; I saw colors like dark blue, white, something approaching from behind that closed… and sank me,” he told CNN in a separate interview. “At that moment, I thought there was nothing I could do.”

Initially, Adrián was concerned that he had run into a killer whale. “We had been talking about orcas shortly before, so I had that in my head,” he confessed to the AP.

But fortunately, he was able to escape alive and uninjured as the whale released him.

Once Adrián surfaced, however, his focus shifted. “I was scared that something might happen to my father too, that we wouldn’t reach the shore in time, or that I would get hypothermia,” he recalled.

Eventually, Adrián’s father was able to reach his son and help him to safety.

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Adrián has since had time to reflect on the encounter with the whale. “It was probably out of curiosity that the whale approached me,” he explained, “or maybe to communicate or something.”

The humpback whale is an endangered species that lives “in all oceans around the world,” according to National Oceanic and Atmospheric Administration (NOAA) Fisheries.

They typically “feed on shrimp-like crustaceans (krill) and small fish,” and can be up to 60 feet in length and 40 tons in weight.