A man was killed and dozens of other people were injured, including two critically, when a tour bus rear-ended a stalled Nissan Pathfinder, and the SUV caught fire on the 60 Freeway in Hacienda Heights early Sunday, authorities said.

The collision on the westbound freeway, west of Azusa Avenue, occurred shortly after 5 a.m.

The SUV had stalled for unknown reasons in the No. 1 lane on the freeway when the tour bus slammed into the back of it. The bus then veered to the right and moved across all the westbound lanes before hitting a guardrail on the shoulder, the California Highway Patrol said in a news release.

The crash left the SUV fully engulfed in flames, trapping the driver inside, the CHP said.

The SUV driver was pronounced dead at the scene, according to the fire department. His identity was not released pending notification of family.

The fire did not spread to the bus, the Los Angeles County Fire Department said.

CHP Officer Zachary Salazar said 63 people were aboard the bus, including the driver, identified by officials as Sui Sheng Du. A total of 32 people on the bus were transported to hospitals.

Of those, 26 had minor injuries, the fire department said.

A passenger on the bus, Joe Runnel, told KTLA Channel 5 that people were “begging for mercy” in the moments after the crash.

“I was thrown from the back seat of the bus to the floor about three or four seats down,” Runnel said. “Glass was on me … there was a lot of hollering.”

The origin of Sunday’s bus trip from the desert area was unclear as of midday. The bus was reportedly headed to Koreatown.

Photos from the scene showed the mangled bus with a shattered windshield leaning along the soft freeway shoulder, with personal belongings and paperwork strewn around it. The burned, damaged SUV was covered in tarps.

Officers do not believe alcohol or drugs were a factor in the crash.

The westbound freeway was fully closed for a few hours after the crash, but some lanes had reopened by 8:30 a.m. and a Sigalert was completely canceled as of 10:20 a.m.

Any witnesses to the crash are encouraged to contact the CHP Santa Fe Springs Area office and speak with investigating officer, V. Guzman or Officer Z. Salazar.

City News Service contributed to this report.