Police are now treating a bushfire impacting Northern New South Wales as suspicious.

Hundreds of NSW Rural Fire Service and NSW Fire and Rescue crews have been battling a bushfire on Busbys Flat Road, Busbys Flat since Friday, October 4.

The blaze has already impacted upon several rural townships, including Rappville, Coombell, Busby Flat Creek, Main Camp and Myrtle Creek, near Casino.

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Homes destroyed

Numerous structures have been damaged or destroyed, with 21 houses confirmed lost,4 damaged, 2 community facilities destroyed, 5 damaged, 35 outbuildings destroyed and 7 damaged.

However, the exact number won’t be known until NSW RFS Building Impact Assessment teams inspect the entire area.

Investigators from Richmond Police District and the NSW RFS are still accessing the fire ground to assess the impacted areas and buildings.

Strike Force established

Following inquiries, detectives from Richmond Police District, with assistance from the State Crime Command's Financial Crimes Squad's Arson Unit and NSW RFS fire investigators, have established Strike Force Cleander to investigate the cause and origin of the fire.

Richmond Police District Commander, Superintendent Toby Lindsay said detectives will work tirelessly to determine the cause of this blaze.

“The NSW Police would like to commend the bravery and service of all NSW RFS volunteers, crews from NSW Fire and Rescue and local police for protecting dozens of properties and livestock,” he said.

“The community of Rappville and other surrounding suburbs have already been struggling with the crippling drought conditions.

“Strike Force Cleander will leave no stone unturned so we can provide answers for the rural communities impacted by this disaster,” Supt Lindsay said.

NSW Rural Fire Service Deputy Commissioner Rob Rogers said crews will continue to remain on the ground for the foreseeable future to bring the blaze under control.

“Cooler conditions are on the way for the area in the next 48-hours which will assist our crews greatly.

Public Information and Inquiry Centre established

A Public Information and Inquiry Centre (PIIC), has been opened to assist members of the public in relation to bush fire information for the Northern Rivers.

The telephone number to call is 1800 227 228.

A number of people remain unaccounted for in and around the area.

Residents who live in the impacted areas should visit the Register.Find.Reunite website (https://register.redcross.org.au) and select ‘Northern NSW Bushfires’ to register their current location.

Members of the public are reminded to delay all non-essential travel in fire affected areas to assist emergency services.

Avoid dangers such as damaged powerlines and the possibility of asbestos in fire-damaged properties.

Health warnings are also in place due to significant smoke in and around areas affected by fire. If it is safe to do so, remain indoors or seek medical assistance if required.

Trauma counselling assistance is available via the Mental Health Access Line (1800 011 511).

Monitor emergency websites and your regular media news source for updated advice and warnings.