Firefighters are dousing hotspots at the site of a northwest Missouri grass fire that damaged up to 1,500 acres of land and briefly spawned a so-called "fire tornado."

Officials say the blaze was largely contained by late Thursday but hotspots likely will continue until the area gets precipitation or colder temperatures. The region is experiencing unusually high temperatures and low humidity.

The fire started when a large mower attached to a hauler malfunctioned and threw sparks, burning mostly on Federal Bureau of Prisons. Two old outbuildings were destroyed but no injuries were reported.

Onlookers captured photos and video of at least one funnel of flames that looked like a small, orange tornado moving across the site.