Three backyards caught fire on Churchill Cres in Whanganui this morning.
Fire and Emergency Whanganui was notified of the fire at 11.50am.
Senior station officer Bryan Coskerie said an elderly man was using an incinerator to burn some rubbish.
"He was unaware of the complete fire ban. He left the fire unattended for a few minutes and when he came back, three backyards were ablaze."
Francisca Webby, who lives at one of the properties that caught fire, said the fire spread within minutes.
"I looked out of the window and I saw a spark hit the backyard and moments later my backyard was ablaze."
She said she is thankful for the fire brigade's fast response.
"We are extremely lucky they got here straight away."
Coskerie said people need to be extremely cautious during total fire bans.
"The conditions are extremely dry and volatile - there should be absolutely no fires. We are very lucky there were no high winds otherwise we'd be in complete danger."
No one was injured.
The entire North Island is now under a total fire ban or fire restrictions. Whanganui, Ruapehu, South Taranaki and Rangitīkei districts all have prohibited fire seasons in place, meaning no fires are permitted, including rubbish fires.