Many of the messages, the authorities said, adopt the flippant, sarcastic chatter often found on online message boards and in-game chats.

The brazen attack sent shockwaves through the area. Police teams and forensic experts rushed to the spot and recovered six bullet casings from the crime scene.

U.S. investigators on Thursday released photos and a video of a person of interest in the fatal shooting of influential conservative activist Charlie Kirk and said they had found the rifle believed to have been used in the politically charged killing.

The phrase, inscribed on an unfired casing tied to the man arrested in Charlie Kirk’s shooting, was popular in Italy after World War II. It has recently resurfaced in a Netflix series and video games.