MADRAS, Ore. (AP) - Firefighters are battling a 640-acre wildfire along the Deschutes River Canyon.

The fire was reported Friday night. It is burning in grassy land about 17 miles north of Madras near South Junction.

The cause of the fire is not yet known.

Four engines, a 20-person hand crew and miscellaneous overhead personnel are expected to fight the fire on Saturday, according to the Central Oregon Interagency Dispatch Center.

The Lower Deschutes River remains open for recreation, but authorities say rafters should use caution when floating through the South Junction area.

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