Story highlights Three teens ordered held without bond in connection with Illinois beating

Delfino Mora, 62, died from blunt head trauma, the Cook County medical examiner says

"I want revenge, but my mom told us not to do anything," the dead man's son says

The family needs money to return the man's body to his hometown in Mexico for burial

A teenager charged with the fatal beating last week of a Chicago man had a video of the attack on his cell phone when arrested Saturday, a video he also posted on his Facebook page, prosecutors said Monday.

Malik Jones, 16, allegedly was playing a game called "pick 'em out and knock 'em out" when he punched Delfino Mora, 62, in his jaw, sending Mora to the ground, where the back of his head was cracked by concrete, a Cook County, Illinois, prosecutor told a judge during a hearing Monday.

Nicholas Ayala, 17, and Anthony Malcolm, 18, used Jones' cell phone camera to record the attack, picking up the "loud crack of his head hitting the cement," prosecutor's spokeswoman Tandra Simonton said.

All three teens were ordered held without bail until their next court date August 3, Simonton said. All three were being charged as adults with first-degree murder, prosecutors said.

Mora, the father of 12, was collecting aluminum cans and scrap metal to sell in an alley near his north Chicago home when Jones chose him as his victim, she said.

"I think I'm going to knock this guy out," Jones is heard saying on the video.

All three teens left the alley laughing, leaving the bleeding Mora on the ground, Simonton said. Jones and Ayala returned a few minutes later to take $60 from his wallet, she said.

A 64-year-old man was allegedly robbed by the teens of $1 a few minutes later, prosecutors said.

Mora died in St. Francis Hospital the next day from cranial-cerebral injury, blunt head trauma and asthma, according to the Cook County medical examiner.

Jones posted the beating video on his Facebook page, and it was seen there by someone who said Jones also attacked him on June 30, Simonton said. That man showed it to Mora's youngest son, Emmanuel, who is a friend of his, and that led police to Jones on Saturday, she said.

"I want revenge, but my mom told us not to do anything," Emmanuel Mora, 20, told CNN affiliate WGN . "God would take care of him and he's going to pay twice."

His older brother, Valentin Mora, told CNN Monday that Emmanuel is too traumatized by seeing the beating video to talk about it.

Mora often walked the streets of his neighborhood, his son said.

"He don't like to stay home," Valentin Mora said. "He wants to bring in extra money. Social Security is not enough."

The family is trying to raise money to pay for the return of Mora's body to his hometown in Mexico for burial. An account for donations was created at Chase Bank in Chicago, his son said.