Firefighters trying to snuff out the biggest wildfire in Kansas history are getting help from military helicopters — and a potential assist from rain or snow.

Two Black Hawk helicopters from the Kansas National Guard have been dispatched in the efforts to contain the persistent prairie blazes in south-central Kansas.

Each helicopter has a 660-gallon bucket that will be used to dump water from local sources onto the flames.

The fire, which began Tuesday and spread north from Oklahoma into Kansas, is blamed for charring at least 620 square miles and destroying at least two homes. No serious injuries have been reported.

The National Weather Service says the area where the fire is located may get one-tenth to a quarter inch of precipitation Saturday night or Sunday morning.