Disturbing new video captures the moment a deranged gunman, who killed a Canadian tourist and injured 13 others at a historic Mexican pyramid, casually walks by with a backpack brimming with ammunition. Moments later, he sets up his weapon and unleashes gunfire, sending terrified tourists fleeing in all directions.

A voice echoes desperately, “Get down! Get down!” as the sound of gunshots reverberates through the air, causing chaos and panic at the ancient site of Teotihuacan’s ruins.

The shooter, identified as 27-year-old Mexican national Julio César Jasso Ramírez, who had an unsettling fixation on Hitler, is seen wearing a mask. In the footage, he enters the frame before positioning himself on the Pyramid of the Moon, preparing to launch his deadly attack.

In a frantic scramble for safety, tourists can be seen ducking and running as bullets fly around them, creating a scene of terror and confusion.

“All we could hear were shot after shot… and we didn’t know where they were aimed,” recounted Yazmin Salcedo from Texas. Her husband, Joel Torres, captured the terrifying event on video during their vacation. “That’s why we just kept running and running,” she explained.

Torres, along with Salcedo, was on a family trip with their son and daughter-in-law when he unintentionally recorded the attack while filming the pyramid with a 360-degree camera, they shared with NBC Dallas-Fort Worth.

“He walked in front of us, sat himself down … It wasn’t even a minute. It was less than that when the first shot happened,” Torres said.

“Thank God … there were not more people killed because he really had the opportunity to shoot everybody that he could out there,” he said.

Ramírez shot dead a Canadian woman, while six Americans, three Colombians, one Russian, two Brazilians and one Canadian were taken to the hospital on Monday.

He climbed midway up the pyramid— a nearly 2,000-year-old structure that was once used for ritual human sacrifice — and opened fire with a 1968 Smith & Wesson gun before turning it on himself, Mexican authorities said.

Authorities later found him armed with 58 rounds of unused ammunition.