It was the fourth suspiciously lit grass fire in five days along the river and it ignited around 2pm on Wednesday near the Tracker Riley Cycleway.

Firefighters from Dubbo HQ Rural Fire Brigade were among those who attended the blaze and they took to social media to send a stern message to the public.

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“Crews from all stations work(sic) hard through the afternoon to contain and blackout the fireground which covered both sides of the walking track along the river,” the post read.

“Unfortunately, during the afternoon several members of the public attempted to walk, run or cycle along the track despite active fire, heavy smoke and several fire trucks at work on the track.

“Crews were forced to divert their attention away from the fire to direct the members of the public away from the active fireground for their own safety.”

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Fire and Rescue NSW crews from Dubbo and Delroy were also called to the blaze which burnt grassland on the western side of the river.

“It’s the fourth fire in five days,” Dubbo Station Officer Mick Medlin said.

“We contained the fire to a five-hectare area and we were there for approximately five hours.”

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Station Officer Medlin said the cause of this fire fire, along with the previous fires along the river during the past few days, was suspicious.

“Police are investigating this fire,” he said.