Firefighters say a car crash was the cause of a large fire that broke out north of the Denver International Airport on Saturday afternoon.

The Brighton Fire Rescue District says a vehicle was traveling through the area of E. 120th Avenue and N. Watkins Road around 2 p.m. when it crashed. Fortunately, the people inside the vehicle did not suffer serious injuries, but the fire department says the vehicle’s catalytic converter caught the nearby grass on fire.

The 120 Fire quickly grew, and firefighters responded with engines, brush trucks and water tenders to attack it from multiple sides. Multiple agencies responded to assist as the winds continued to push the fire across the grassland.

It covered around 237 acres by the time firefighters brought it under control around 3:30 p.m. BFRD says firefighters continued to put out hotspots and monitor a large cottonwood tree that was smoldering nearly 30 feet up the trunk.

With Independence Day approaching, the fire rescue district shared a reminder that a single spark can ignite a fast-moving grass fire. They added that aerial fireworks are illegal in Brighton and pose a serious fire risk in the current conditions.