Mexican authorities on Tuesday said a gunman who killed one person and injured several others at the Teotihuacan pyramids in central Mexico had carried materials related to attacks in the United States.

One Canadian tourist was killed while visitors from Canada, Colombia, Russia, Brazil and the United States were among those injured in the Monday shooting. The assailant, who acted alone, shot and killed himself, authorities said.

Mexican authorities said the gunman carried several books and handwritten notes that referenced attacks in the United States in April, 1999.

The attack in question was likely the 1999 school shooting in Columbine, Colorado that left 16 dead and 23 injured.

Monday was the 27th anniversary of the Columbine massacre that marked the start of an era of school shootings in the US and a fierce national debate about gun control that continues two decades later.

A state official told the AP the gunman also possessed an AI-altered photo depicting him with the Columbine attackers.

What else did Mexican officials say about the suspect?

"This act was not spontaneous," Jose Luis Cervantes, attorney general of the State of Mexico, said at a press conference alongside President Claudia Sheinbaum.

Cervantes said the gunman had a "psycopathic profile" that is "characterized by a tendency to copy situations that occurred in other places, at other times and involving other figures."

The suspect was a 27-year-old man from the southwestern Mexican state of Guerrero, according to officials.

Investigators found a gun, a knife and a bag containing 52 rounds of ammunition at the scene.

He was carrying a tactical-style backpack with an analog cellphone and bus tickets, Cervantes said.

The shooter began firing at tourists while atop the Pyramid of the Moon in the archaeological complex.

The attorney general said some people lay motionless on the ground to hide, while others fled the scene.

The shooter took his own life after security forces arrived at the scene and shot him in the leg.

Edited by: Louis Oelofse