Investigations are continuing into the cause of a fire that left a Merivale garage gutted and three people in Tauranga Hospital.

The five-by-three metre standalone garage, at a Fraser Street property, was seen to be fully ablaze by neighbours at about 3.40pm on Sunday.

The charred remains of the Fraser Street garage. Photo: Bruce Barnard.

Greerton Fire Brigade station officer Paul van Kol says firefighters from Greerton and Tauranga, along with St John Ambulances, attended the scene.

'It was a storage shed and had lots of stuff in there,” says Paul.

'It was free standing with a car port attached to it, but we stopped it from spreading pretty quickly.”

Paul says an occupant of the house had been in the shed just prior to the fire igniting, but the cause is still under investigation.

A fire safety officer is due to inspect the charred scene today.

Paul says two occupants of the house were taken to Tauranga Hospital for observation due to smoke inhalation, and one for radiated heat burns.

Photos: Alicia Joanne Hovell.