Two women who put out a rubbish bag fire in Napier on Monday night say it could have destroyed a local business if they hadn't seen it.

The fire, one of two in the area, is another of a spate of deliberately lit rubbish fires in the city which have frustrated firefighters and police.

Sianalee Watene said she and her cousin Miri Hungahunga were walking home just after 8pm when they spotted a "little flame" outside Bay Audiology on Raffles St.

She said they put out the rubbish bag fire using a stone they found.

A rubbish fire on Raffles St on Monday night. Photo / Supplied
A rubbish fire on Raffles St on Monday night. Photo / Supplied

"Then we just used our foot to keep the flames down."

Firefighters arrived just after the pair extinguished the flames.

She said she thought Bay Audiology may have caught on fire had no one seen the burning rubbish bag in time.

The pair then saw another fire around the corner, which the police were attending.

Hawke's Bay Area Commander for Fire and Emergency New Zealand Ken Cooper said they had been called to two deliberately lit fires in Napier South on Monday night.

"We responded to two incidents of deliberately lit unlawful fires."

He said there has been an increase in rubbish fires in Napier recently.

"We have had a spate of these incidents over the past two to three weeks, and it's actually becoming quite a risk to us."

He said they were asking the community to give them a hand minimising the potential for rubbish fires to happen.

"So, not putting your rubbish out until the morning it'll be picked up."

He said they are asking commercial businesses to not put out combustible materials, especially beside buildings and putting locks on skip bins.

"We're doing some preventative stuff now, so firefighters are out going round the commercial and industrial areas, doing spot inspections and talking to business owners around good housekeeping to minimise the potential for that risk."

He said they also have a close relationship with the police, who they are working with to identify the people responsible for the fires.

He said main concern was that the rubbish was being used to cause further damage to property.

"The actual rubbish, yes is a hazard, but the concern for us is they are using it to try and start larger fires.

"Or they are putting the rubbish against power poles, therefore damaging the power network.

"The other things is it is potentially taking us away from other work."

He said as long as members of the public feel safe doing so, putting out small fires in outdoor spaces is fine, as Watene and Hungahunga did.

"If there is no risk to yourself we're quite happy to individuals to extinguish small fires out in the open.

"But certainly nothing internally."

A police spokesperson confirmed they received to calls regarding the fires on Monday night.

"A report was taken and police are making inquiries."