Authorities believe arson caused the fire, which swept through neighbourhoods on the outskirts of Valparaiso.

Helicopters dropped water on the outskirts of the Chilean port city of Valparaiso on Wednesday to extinguish a fire that has destroyed dozens of homes.

Residents in the city’s Rocuant and San Roque hills sifted through the ruins of their homes after the fire, fanned by strong winds, swept through their neighbourhoods on Tuesday.

Residents had been evacuated and there were no reports of casualties.

Authorities believe arson caused the fire.

“We’re not certain, but everything indicates that yesterday’s fire was intentional, and began in an area quite close to the homes,” said Ezio Passadore, emergency manager for Valparaiso.

A man looks at the destruction caused by a forest fire at the Rocuant hill in Valparaiso, Chile [Pablo Rojas Maradiaga/ AFP]

Many homes in the low-income neighbourhoods where the fire occurred do not have running water and get their supply from tankers a couple of times a week.

Wildfires have affected parts of Valparaiso several times in the last month as Chile contends with its worst drought on record.