Thousands of Hawaii residents raced to escape homes on Maui as blazes swept across the island, destroying parts of a centuries-old town and killing at least 36 people in one of the deadliest US wildfires in recent years.

The fire took the island by surprise, leaving behind burned-out cars on once busy streets and smoking piles of rubble where historic buildings had stood in Lahaina Town, which dates to the 1700s and has long been a favourite destination of tourists.

Crews battled blazes in several places on the island on Wednesday, and the flames forced some adults and children to flee into the ocean.

At least 36 people have died, according to a statement from Maui County late Wednesday that said no other details were available.

Officials said earlier that 271 structures were damaged or destroyed and dozens of people injured.

The 2018 Camp Fire in California killed at least 85 people and virtually razed the town of Paradise.

Officials warned that the death toll in Hawaii could rise, with the fires still burning and teams spreading out to search charred areas.

Lahaina residents Kamuela Kawaakoa and Iiulia Yasso described a harrowing escape under smoke-filled skies on Tuesday. The couple and their 6-year-old son got back to their apartment after a quick dash to the supermarket for water, and only had time to grab a change of clothes and run as the bushes around them caught fire.

“We barely made it out,” Kawaakoa said at an evacuation shelter on Wednesday, still unsure if anything was left of their apartment.

As the family fled, a senior centre across the road erupted in flames. They called 911, but didn't know if the people got out. As they drove away, downed utility poles and others fleeing in cars slowed their progress. “It was so hard to sit there and just watch my town burn to ashes and not be able to do anything," Kawaakoa, 34, said.

As the fires rage, tourists were advised to stay away, and about 11,000 visitors flew out of Maui on Wednesday, with at least another 1,500 expected to leave on Thursday, according to Ed Sniffen, state transportation director.

Officials prepared the Hawaii Convention Centre in Honolulu to take in the thousands who have been displaced.

Maui County Mayor Richard Bissen Jr. said the island had “been tested like never before in our lifetime.”

“We are grieving with each other during this inconsolable time,” he said in a recorded statement. “In the days ahead, we will be stronger as a ‘kaiaulu,’ or community, as we rebuild with resilience and aloha.”

The fires were whipped by strong winds from Hurricane Dora passing far to the south.

It's the latest in a series of disasters caused by extreme weather around the globe this summer. Experts say climate change is increasing the likelihood of such events. (AP)