The group went outside after the restaurant closed, where they were confronted by 48-year-old Nelson Hernandez Mena, who began to threaten them.
He faces charges of first-degree murder, attempted murder, and aggravated assault with a firearm.
When Cruz defended his friends, Mena pulled a handgun from his trousers and fired several shots, killing Cruz and wounding another man in the ankle, who told investigators he believes he was targeted because he is gay. Cruz stepped forward to defend his friends and was shot and killed, the witnesses said.
"The victim who survived the gunshots believes Hernandez Mena became angry when he got the phone number of one of Mena's friend [sic] and that he was targeted because he is gay, according to the police report", local Fox affiliate WFLX reports. Cruz stood up to the gunman and was fatally shot-but he might have saved his friends' lives.
"I hate you damned gays, I'm going to kill you all here", Nelson Hernandez Mena allegedly said before shooting 22-year-old Juan Javier Cruz outside of a Salvadoran restaurant early Sunday morning. Mena appeared shortly after and when asked what happened, he told his friend "nothing" and "asked him to take him somewhere", according to the arrest report.
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"He is traumatized, he can't sleep", she said of her nephew, who witnessed the attack.
Hernandez Mena told investigators he drank 15 to 20 beers that night. "I miss him, he's my son, it hurts", she added.
A spokesperson for the Palm Beach State Attorney's Office told the Sentinel that it was still too early in the case to say whether Mena would be charged with a hate crime.
He added that he recalled pulling his gun out, but that Cruz wasn't his intended target.
Mena has been denied bond.
Cruz's sister, Nancy, started a GoFundMe page to raise funds for her brother's funeral expenses.