A wildfire sparked by a crash involving a cement truck and a tour bus along Highway 140 in Mariposa County forced evacuations and burned hundreds of acres Tuesday, according to authorities.

The wildfire, dubbed the Colorado Fire, ignited after a cement truck overturned and collided head-on with a small tour bus, according to the California Highway Patrol. New video obtained by ABC30 shows the moments before and after the collision.

The tour bus driver told ABC30 he was returning the vehicle to San Francisco when the crash occurred and that no passengers were on board. He said he was shaken by the incident but grateful to be alive.

Video from the scene shows the tour bus coming to a stop while the cement truck slides, appears to strike a guardrail and then collides with the front of the bus.

According to CHP, the cement truck was traveling east on Highway 140 when it entered a curve, crossed lanes, overturned and crashed into the bus. The crash then sparked the fast-moving wildfire.

El Portal resident Nick Desin said he had just gotten gas when he saw the smoke.

"I saw the overturned cement mixing truck. There were a few cars parked up in a turnout right by it. While we were there, Highway Patrol rolled up and sent us back up the hill," Desin said.

The fire burned brush and trees, charred hundreds of acres and prompted evacuation orders.

Aerial video shared with ABC 30 by KCRA showed a large plume of smoke rising from the fire area.

CAL FIRE spokesperson Jamie Williams said firefighters faced multiple spot fires as they worked to contain the blaze.

"We did have multiple spot fires on this fire. Firefighters worked really hard to contain those," Williams said.

Firefighters also faced challenges because of the area's steep and rugged terrain.

"Access is very difficult for the firefighters, but they are working really hard to gain the upper hand on this fire to get people home as quickly as possible," Williams said.

CHP officers said the bus driver was the only person inside the tour bus at the time of the crash and was not injured.

As of the latest update, the Colorado Fire had scorched 250 acres and remained 0% contained.

The following areas are under mandatory evacuation orders:

The following area is under an evacuation warning:

CAL FIRE
CAL FIRE

The Mariposa Health and Human Services Agency and the American Red Cross established a Temporary Evacuation Point at New Life Calvary Church off Cole Road to provide assistance and resources for evacuees.

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