Work continues to formally identify two elderly men killed in the blaze that tore through Yarloop, Western Australia, and destroyed 128 homes. But a third person feared missing in the bushfire south of Perth has been found alive.

West Australian police said it was possible further missing person reports could be made as time went on.

They have urged all residents from fire-affected areas to register with the Australian Red Cross.

Human remains, believed to belong to two men aged 73 and 77, were found at two burnt-out homes in Yarloop on Saturday evening.

Malcolm Taylor is believed to be one of the men. A family member said no one had not heard from him since Thursday evening before the blaze ravaged the small town, which has a population of 545.

When she last spoke with the 73-year-old, who requires a hearing aid, he said he was going to stay at his house.

Family members fear Malcolm Taylor, 73, who stayed in the bushfire-ravaged town of Yarloop to defend his home, may have perished in the blaze. Photograph: Facebook/AAP

“He goes to bed early, around 7.30pm, so we’re worried that he turned off his hearing aid and went to sleep and then the houses went up so quickly,” she said. “If Malcolm was all right, he would have rung someone by now.”

The state’s opposition leader, Mark McGowan, tweeted his support for the victims late on Saturday night: “Terrible news tonight of lives lost in the South West fires. Thoughts are with family, friends and neighbours of those tragically taken.”

The premier, Colin Barnett, visited one of the evacuation centres on Saturday.

An emergency warning remains in place for a large part of the region, including east of Waroona, Hamel, Yarloop and surrounding areas.

But more favourable conditions has seen the alert level drop to a watch and act for some areas including Waroona, Harvey, Cookernup, Preston Beach and Lake Clifton.

The Department of Fire and Emergency Services says forecast weather conditions are expected to assist firefighters on Sunday, but the blaze is still uncontained and uncontrolled.

More than 72,600 hectares have been burnt since the lightning-sparked fire began on Wednesday.

At least 143 properties, including the 128 houses in Yarloop, have been destroyed, including sheds, caravans and community buildings.

Disaster assistance will be available for victims under the jointly-funded Commonwealth-State Natural Disaster Relief and Recovery Arrangements.

Four firefighters have been injured battling the blaze, while 60 firefighters, five paramedics and three management support staff from NSW are assisting local crews battling fatigue.

Several roads and recreation sites remain closed, with dairy farmers forced to dump thousands of litres of milk.

Nicole Ferraro said her father and brothers stayed to defend their properties and managed to save most of the herd, their homes and dairy, while the rest of the farm suffered “a blackened fate”.

“For the short term, their main focus is the well-being of the animals, keeping the cows milked and fed, as well as the supply of diesel which is needed to run the generator to keep the dairy operational and the milking herd healthy,” she wrote on Facebook.

Western Power says thousands of properties remain without power but burnt trees and debris in danger of collapsing must be cleared before crews can rebuild the network.

About 835 people have registered at two evacuation centres.

People wanting to help can make monetary donations through the Lord Mayor’s Distress Relief Fund and the state government has already committed $1m.

Two New South Wales-based helicopters had left for Western Australia to help battle the fire. More than 60 firefighters from NSW have been deployed to help fatigued crews battle a blaze raging since Wednesday.

Meanwhile, a total fire ban has been declared for parts of South Australia thanks to hot, dry and windy conditions.

Temperatures were tipped to reach close to 40C in parts of the state on Sunday, including 38C in Adelaide.

The Country Fire Service said “very hazardous fire weather conditions” were predicted in areas including northwest pastoral, eastern Eyre peninsula, mid north, Mount Lofty ranges, Yorke peninsula, riverland, murraylands and lower south east.

Residents of those regions were told to implement their bushfire survival plan.

