(KTLA) At a news conference announcing the arrest of Tyler Robinson for the alleged assassination of conservative activist Charlie Kirk, authorities revealed that bullet casings found in the rifle that was used in the attack were engraved with a series of messages.

One unfired casing was marked with the Italian phrase, “O bella ciao, bella ciao,” Utah Gov. Spencer Cox said.

“O bella ciao, bella ciao” is a phrase from the famous anti-fascist folk song, “Bella Ciao,” which was popularized by Italian partisans who fought against fascist forces during World War II.

Today, it remains a rallying cry for activists and is a hallmark of Italy’s Liberation Day, which celebrates the fall of Benito Mussolini’s regime. The song has also gained new attention for its use in the popular Netflix series “Money Heist.”

Literally, it translates to “Hello, beautiful,” or “Goodbye, beautiful.”

Other casings bore different messages. One unfired casing read, “Hey fascist! Catch!” and featured a series of arrow symbols, according to authorities. Another had the taunting message, “if you read this, you are gay LMAO.”

Robinson, 22, was arrested on suspicion of aggravated murder, felony discharge of a firearm, and obstruction of justice, according to a court affidavit. A judge ordered that he be held without bail, with formal charges expected early next week.

Cox said Robinson had become “more political” recently and had indicated to a family friend that he was responsible for the shooting.

Kirk, 31, the co-founder of the youth organization Turning Point USA, was killed by a single shot while speaking to thousands of students on Wednesday on the campus of Utah Valley University in Orem.