A man who was trying to cut down a power pole with a chainsaw has been arrested after a stand-off with police.
Police say the man's clothing caught fire when he was tasered after he threw petrol at three officers at Riverstone on Tuesday morning.
"(Police) attempted to negotiate with the man. During that negotiation the man poured petrol, threw petrol toward police," Detective Inspector Gavin Rattenbury told reporters at the scene.
Officers attempted to subdue the man with capsicum spray and a Taser, but the petrol ignited and the man caught fire.
Police extinguished the flames before the man went back inside his Regent Street home and refused to come out.
The man surrendered after about 45 minutes of negotiations and was taken to Westmead Hospital under police guard.
He's being treated for minor burns and is expected to be charged later on Tuesday.
A leading senior constable is also being treated at Blacktown Hospital after petrol was splashed in his eyes.
"He's a good police officer and from all reports he's OK, and that's a good thing," Det Insp Rattenbury said.
Rangers have been called to the property to remove a number of dogs, believed to be about eight rottweilers.
"We obviously need to conduct an investigation and it's difficult to do that whilst dogs are roaming around the premises," Det Insp Rattenbury said.
Investigations are continuing into what prompted the incident, but police believe the man was in conflict with an energy provider.
A nearby resident told AAP the man had his power cut off and retaliated by trying to cut down a power pole with a chainsaw.
"When police arrived he threw a petrol bomb into the face of one of the policemen," she said.
Police wouldn't say whether the man was known to them, but the neighbour said he had been causing problems in the street on and off for 15 years, and had allegedly fired shots from the home in the past.
Nearby Riverstone Public School went into lockdown during the incident.
