Mexico City, Mexico

Julio Cesar Jasso Ramirez, the 27-year-old gunman behind Monday's shooting at Mexico's famed Teotihuacan pyramids, drew inspiration from pre-Hispanic sacrifices and the notorious 1999 US shooting at Columbine High School, according to investigators.

The attack, which ended with the assailant taking his own life, injured 13 people at the tourist attraction, and left a Canadian woman dead.

Mexico State Prosecutor Jose Luis Cervantes Martinez said Jasso Ramirez lived in Mexico City, about 50 kilometers (31 miles) from the site, and "made preliminary visits on multiple occasions to the archaeological site, stayed in hotels near the site ahead of time, and from there planned his violent acts."

A preliminary investigation into the attack found several ties to the mass shooting which took place exactly 27 years earlier at Columbine High School in the US state of Colorado.

"The collected evidence...reveals a psychopathic profile of the attacker, characterized by a tendency to copy situations that happened in other places at other times by other people," Cervantes said at a press conference Tuesday.

The 1999 attack by students Eric Harris and Dylan Klebold killed 12 students and one teacher, with 20 others injured from the gunfire.

Reports by Mexican media said authorities found among the shooter's personal belonging an AI-generated image that showed Jasso Ramirez alongside Harris and Klebold.

And the shirt Jasso Ramirez wore Monday when he arrived at the pre-Hispanic heritage site to carry out the attack was similar to one worn by the Columbine assailants, according to authorities.

- Sacrifices, not photos -

Witness accounts of the attack point to another possible influence regarding the location chosen by the shooter: the human sacrifices by pre-Columbian civilizations in the Americas.

Jacqueline Gutierrez, an American tourist visiting Teotihuacan the day of the shooting, told Mexican broadcaster Milenio: "One of the things he was saying to us was that this is a place for sacrifices, not for your little photos...and that it's the anniversary of the Columbine massacre."

Gutierrez was at the site with her parents and boyfriend when "14 minutes of terror" broke out, with nowhere to escape.

"We couldn't move or we'd fall down the pyramid...if he had wanted to kill us all, he would have," she continued, adding that he said he had been planning the attack for three years.

Investigators maintain the incident was the result of a lone gunman with no collaborators, with a search of his possessions yielding "literature alluding to attacks and to figures connected to this type of violence," Cervantes said.

bur-sem/lp/dga/jgc/dw