Police and fire authorities to look into what caused large scrub fire at Oceanview Speedway

The fire was visible from the other side of the river, with smoke filling the sky. Photo / Daniel Hill

An investigation by police and fire authorities will look into what caused a large scrub fire at the Oceanview Speedway over the weekend.

The speedway's club secretary, Maryann Roberts, said the fire started on the hillside motorcycle track before 8pm on Saturday night.

Photos show the fire was visible from the other side of the river, with smoke filling the sky.

Roberts said she believed the fire could be attributed a large group of children playing with fireworks near the hillside track around the time it started.

"It is illegal to sell fireworks to children that age, so I don't know how they got hold of them."

The speedway was the venue for Whanganui's only public fireworks display - the Tradezone Fireworks spectacular, on Saturday night - and hundreds of people attended the event, which included stock and saloon car racing.

Roberts said it was fortunate the rural fire service was already in attendance and were able to get to the blaze quickly.

Six Whanganui fire crews responded to the callout, and the last crew departed at about 10pm, a FENZ spokesperson said.

"It still took quite a while to get it under control, and there was concern that vehicles were in the path of the fire," Roberts said.

"The whole idea of having a public display was to avoid these problems, so this was really disappointing."

Roberts said firefighters did an excellent job of containing the fire and keeping the public safe.

"We had a good water supply with our water truck at the venue, which helped control the fire in the early stages.

"Thankfully, we didn't have to stop the event and send everyone home, because we had a big crowd, and for the most part, it was a great event."

Police were called to investigate the cause of the fire and a police spokeswoman said they were notified of a vegetation fire at 8pm.

"Fire and Emergency New Zealand (FENZ) advised police that the fire appeared suspicious. Police will be liaising with FENZ to see what can be determined regarding the cause and circumstances," she said.