"It was routine maintenance," Mayor Rod Buhr said. "Nothing sinister, just routine maintenance."

Some residents expressed outrage that they had lost art done by local children through a hepatitis awareness program.

"I am very disappointed," one resident said.

"That was council approved and this was done by our youth in Wellington and without our knowledge, all sprayed over."

It's understood council had already organised the purchase of materials for community organisations to put new paintings up in the future.