Following public pleas last week on social media by his brother to help locate him, 21-year-old Christopher Liang appears to have met a tragic end while on an "erratic" road trip from the Bay Area.

The University of San Francisco student rented a Tesla Model 3 on Monday, February 28, apparently telling friends and family that he was driving south to his hometown of Irvine — a trip his family saw as "impulsive," when Liang had classes to attend in San Francisco. Not long after, friends lost contact with him, and both his cellphone and the car went offline — with the Tesla's last known location being a super-charging station in Firebaugh, just off I-5. The rental was due back in SF on Wednesday, March 2.

"I am concerned for his life," his brother, Jerry Liang, wrote in a Thursday Instagram post. "The erratic nature of this trip combined with his mental health issues has made our family extremely concerned for his safety. This is his first time driving since he got his license in March and he has never booked a hotel in his life. I'm terrified and heartbroken. I’ve tried ALL I could with the police but to no avail."

The family offered a $25,000 reward for information about Liang's whereabouts. And on Friday, his brother told KCBS Radio that "everything suggests that he's incapacitated."

Then, on Saturday, authorities in Fresno County discovered the Tesla overturned in a ravine just west of his last known stop, on Panoche Road. And Christopher Liang's remains were inside the car. Per the Chronicle, the car was found down a cliff in a dry riverbed.

As KRON4 reports, officials have not confirmed Liang's cause of death. Jerry Liang has since posted a message saying, "We greatly appreciate everyone’s help and prayers. We ask that everyone respect our privacy as we go through this difficult time."

Investigators will likely be looking into the whereabouts of the car in the hours before it went offline — and it sounds as though, after charging the car in Firebaugh, which is south of Los Banos, Liang may have just headed west on Panoche Road and crashed almost immediately afterwards.

Jerry Liang said to KCBS on Friday that the situation was baffling to the family because his brother, a senior at USF, had been recently been interviewing for jobs and the process was going well. He even stopped on Monday, while charging the Tesla, to participate in a remote interview.

"Those opportunities are important to him. Why would he [now] make himself inaccessible? He had plans," Jerry Liang said. He added that the only explanation was that "This could be a sudden worsening of his mental health issues," saying that his brother had never done anything like this before.

USF President Paul J. Fitzgerald put out a statement saying, "We send our deepest condolences to his family, who were anxiously seeking information through social media and media reports in the days Chris was missing. As his USF community offers comfort and support, we pray that Chris's family, friends, classmates, and professors — who are experiencing profound loss and sadness in the face of many questions — will find solace and peace."

Previously: SF College Student Goes Missing After 'Impulsive' SoCal Trip

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