LOS ANGELES (CBSLA.com) — The beating death of a Chinese USC graduate student, who was attacked while walking home and was found hours later inside his apartment, has led to a “series of arrests”, according to authorities.

A late-afternoon news conference took place at 4:30 p.m. at LAPD headquarters, at which some details of the arrests were announced.

Xinran Ji, a 24-year-old electrical engineering graduate student at the University of Southern California, was found dead at about 7 a.m. on Wednesday, July 24, in the City Park apartments, located in the 1200 block of West 30th Street.

Ji was actually attacked at around 12:45 a.m. while he had been walking home near 29th Street and Orchard Avenue, according to Los Angeles Police Department Lt. Andy Neiman.

Jonathan Del Carmen, 19, Andrew Garcia, 18, and three juveniles are reportedly included in the arrests in connection. Four of the five arrested individuals are charged with murder with special circumstances, assault with a deadly weapon, and attempted robbery.

Following the attack, Ji managed to walk back to his apartment, leaving a trail of blood which showed the path he took.

Ji was struck with an unknown type of “blunt-force object”, according to Lt. Neiman. Ji had reportedly been studying with a group, and had just walked a friend home before heading toward his own residence at the time of the attack.

“We can say that we made (arrests), and it’s four individuals,” Commander Andy Smith said in the press conference. The minors arrested and charged under ‘special circumstances’ may make them eligible under penalty, if convicted, to receive the punishment of death.

While four arrests had been made initially, authorities believe there may have been five attackers.

“As (Ji) was walking home, he was set upon by a group of individuals, we believe five,” Cmdr. Smith said. “And those five individuals accosted him and beat him severely in what we believe may have been an attempted robbery.”

Furthermore, Commander Smith said that he believes the group arrested in connection with Ji’s death may have been involved in another robbery in Dockweiler Beach.

An arrest made in connection with that robbery, police suspect, brings the arrest total to five in connection with Ji’s death. While police suspect that the five individuals arrested may have been involved in a larger crime spree, the fifth suspect arrested was a 15-year-old girl.

LAPD stated that, among other tools, license plate readers were instrumental in tracking down the suspects.

Police do not believe the attackers have any gang-related ties.

Students on campus put together a number of tributes as a memorial for Ji.

“I’m happy that they made arrests,” one student said. “I’m happy that someone got caught.”

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