Smoke is expected to be visible for hours near Antioch due to a vegetation fire burning on an island near the Sacramento and San Joaquin rivers confluence, firefighters said. 

The Rio Vista Fire Department said the fire was burning on Lower Sherman Island Wildlife Area, an area accessible only by boat. 

Crews said there were no life safety concerns and the fire would burn to the water line and self-extinguish. But smoke is expected to be visible for hours Sunday afternoon. 

It’s unknown how the fire was started. 

The Lower Sherman Island Wildlife Area is about 3,100 acres of riparian marshland with willows and cottonwoods. It’s known for viewing wildlife and bird hunting.  

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