Watch: Two adults, two minors charged in beating death of USC graduate student

The parents of a slain USC student from China are expected to arrive in Los Angeles late Wednesday, their trip delayed for almost a week because the U.S. visa system crashed, according to a family friend.

Xianren Kong, the family friend, said in a statement on the couple’s behalf that their biggest wish now is to claim the body of their only child.

“They have had to cancel their airline tickets several times,” he said.

A State Department official said she was prohibited from commenting specifically about the couple's case, but she acknowledged that problems with the system that processes non-immigrant visas had caused a “significant document backlog.”

More details about Xinran Ji's death emerged as prosecutors filed charges Tuesday against the suspects, identified as Jonathan DelCarmen, 19; Andrew Garcia, 18; Alberto Ochoa, 17; and Alejandra Guerrero, 16.

The murder case carries a special-circumstance allegation that Ji was killed during an attempted robbery, allowing prosecutors the option of seeking the death penalty against DelCarmen and Garcia.

Ji, a 24-year-old engineering student, was walking to his apartment near USC about 12:45 a.m. Thursday when authorities said he was attacked with a baseball bat. Despite sustaining a head injury, authorities said, Ji managed to make it home to his 30th Street apartment. A roommate found his body later that morning.

Evidence at the scene of the assault indicated Ji had struggled to get away from his attackers, according to two law enforcement sources familiar with the investigation. The sources, who were not authorized to speak publicly, said detectives believe he was then beaten a second time.

A criminal complaint alleges Garcia, Ochoa and Guerrero used a bat and wrench. A coroner's report are pending.

Because they are minors, Ochoa and Guerrero will not face the death penalty, but prosecutors said they could be sentenced to life in prison without parole if convicted. California law gives prosecutors the option in certain crimes, including murder, to charge a minor as an adult.

After a court hearing Tuesday, Garcia’s relatives insisted he was innocent and incapable of committing such an attack. His mother was tearful as she defended her son.

“My son is a good boy. He had no intention of this happening,” Rosalie Garcia said. “His friend picked him up after dinner. He was going to the beach.”

The defendants remain jailed without bail. Their arraignment was postponed until Aug. 12.

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