Streamer HMBL Zayy's Motorhome Totaled in Highway Wreck After He Walks Across America

HMBL Zayy's cross-country victory lap came to a screeching halt when his motorhome was obliterated on the highway -- just days after he wrapped up his epic fundraising walk across America and started the trip back to the East Coast.

Zayy tells TMZ ... the accident happened Tuesday in California, just hours after Zayy's pal Deejay began driving the Chevrolet motorhome back to Philadelphia.

The vehicle was being driven east on I-10 when it rammed into the back of a semi-truck, according to the California Highway Patrol. Deejay then lost control and traveled into the dirt center median, where the vehicle came to a stop, authorities say.

Deejay was treated for minor injuries at John F. Kennedy Memorial Hospital in Indio ... and Zayy tells us Deejay has since been discharged from the hospital.

Zayy was flying home when the accident happened ... so he's safe. However, the motorhome is totaled, and his dog, Milo, ran away during the crash.

The streamer and activist tells us he's currently driving across America to learn more about the status of his vehicle and search for his beloved pup, who you can see smiling in the cart below.

ICYMI, Zayy livestreamed nearly every step of his travels from Philadelphia to the Golden State and raised nearly $200,000 to help fund a trade school in his hometown for high school graduates who may not have the support to attend college.

He set off in March and completed the trek on July 27 ... and his buddy Deejay and Milo were right there alongside him in their trusty motorhome.

Zayy faced a setback in April as well when he landed in the ER after a car hit him while walking -- and livestreaming -- in Indiana. But he healed up and trudged along.