Updated

Four teens were charged Tuesday with murder in the beating of a University of Southern California graduate student with a baseball bat and wrench as he walked to his off-campus apartment after meeting with a study group.

Two of the suspects were juveniles charged as adults in the slaying of Xinran Ji, 24, an engineering student from China who was attacked early Thursday. He was able to make his way to his apartment despite being hit in the head with the bat. A roommate discovered him dead hours later.

The defendants — 17-year-old Alberto Ochoa, 16-year-old Alejandra Guerrero, 18-year-old Andrew Garcia and 19-year-old Jonathan Del Carmen — will be arraigned Aug. 12 on one count each of murder with a special circumstance of murder during an attempted robbery.

Garcia, Ochoa and Guerrero also face a special allegation for personally using a dangerous weapon — the bat and wrench.

In 2012, two USC students from China were fatally shot during an off-campus robbery also during the early morning.

"For any family this is a horrible tragedy, but it's magnified by the fact that these Chinese families have sent their children so far away expecting that this was the best possible thing ... and now he's gone," Clayton Dube, executive director of the USC U.S.-China Institute, said about Ji.

Dube, who informed Ji's mother of her only child's death, said the university and the U.S. and Chinese governments were working to get Ji's parents to Los Angeles from Hohhot, the capital city of Inner Mongolia in northern China.
Ji's parents, Ji Songbo and Du Jinhui, said in a statement Tuesday that they are struggling to get visas.

They also said they are "deeply concerned" about students at the university, especially those from China.

"We hope that USC can enhance security and guarantee the safety of USC students," they said. The statement mentioned the two Chinese students killed in 2012 and urged the school to learn from those deaths and Ji's.

"We do not want to see another incident like this," they said. "No parents should have to bear this pain."

Ji had excelled at one of China's best universities and won a scholarship for excellence in research and innovation, according to the university. He also won a prize in Zhejiang University's mathematical modeling contest. Ji was an avid photographer, cyclist and enjoyed badminton.

He came to California several years ago on a tour. It was then that Ji decided he wanted to attend graduate school in the U.S. and he enrolled in fall 2013.

Ji had just escorted a study partner home when he was attacked, Dube said.

The consulate general of The People's Republic of China in Los Angeles called Ji's death cruel and said it was concerned about student safety. Students were reminded to take extra security precautions and representatives reached out to U.S. authorities to take measures to ensure the safety of Chinese students, according to a statement from the consulate.

Meanwhile, Chinese students traded messages of sadness and shock and a Taiwanese student association sent out a long message with security tips.

Attorney Daniel Deng, who is representing the family of the students killed in 2012 on a pro bono basis, urged the Chinese government to declare USC an unsafe place to study.

The attack prompted USC to review its program for educating foreign students about safety issues, said USC Department of Public Safety Deputy Chief David Carlisle.