Firefighters battle vegetation fire at Chino Hills State Park

Firefighters battled a vegetation fire at Chino Hills State Park on Monday. 

It was first reported a little before 3 p.m. in the 4700 block of Sapphire Road in Chino Hills, according to the Riverside County Fire Department. 

Crews said that the fire had burned about three acres as of 8 p.m., but that at its peak there was a potential to spread to up to 25 acres due to strong winds blowing in the area. They say that gusts currently tracked at 14 mph in a southwesterly direction, but that some strong gusts were reaching 21 mph. 

Sapphire Road was closed as they continued their battle against the flames.

It's unclear how the fire started.

No injuries have bee reported and no structures were damaged.