Emergency services were called to the blaze at 11.26pm on Monday, December 16 and Bonny Hills Rural Fire Brigade captain Glenn Dunn said crews arrived to find the toilet block engulfed by fire.

It took crews about 15 minutes to control the fire.

Bonny Hills Progress Association president Roger Barlow said the community was absolutely devastated by the news and it couldn't have happened at a worse time, with the start of the holidays.

"We are all in disbelief that someone could have done this," he said.

In September a mural was painted on the side of the amenities block.

Port Macquarie-Hastings artist Kim McLean's design was chosen as the winning creation from the mural design competition, launched by Port Macquarie-Hastings Council in partnership with the Bonny Hills Progress Association (BHPA).

Mr Barlow said while the amenities block can be replaced, the mural was irreplaceable.

Port Macquarie-Hastings Council staff are making the area safe and will be providing temporary facilities for the holiday period.

Police are seeking information from the community in relation to the incident at Rainbow Beach.

To report information please ring Port Macquarie Police Station on 6583 0199 or Crime Stoppers on 1800 333 000.

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