A 'firenado' is filmed burning in US field

This incredible clip of a "firenado" has been filmed by firefighters in the US.

It happens when winds mix with smoke and flames.

The fire burned around seven acres of land but, thankfully, no injuries were reported.

Fire crews in the state of Oregon managed to put out the blaze after about an hour.

They think it was caused by farming equipment cutting the field.

Video courtesy of Cornelius Fire Department.