A portable heater sparked the blaze that killed a 62-year-old woman with disabilities in Melbourne’s inner west, fire investigators have determined.

The woman, named Gaye, was found dead in the upstairs bedroom of her West Footscray home when fire crews arrived shortly after 12.30am on Sunday.

Towels were left near a portable heater, it’s believed, prompting the Metropolitan Fire Brigade (MFB) to renew fire safety warnings.

Gaye’s carer, 69-year-old Leslie, escaped through the front door with minor injuries while screaming for her friend.

“[Leslie] was just screaming that there was somebody upstairs,” a neighbour told reporters at the scene.

Inside the West Footscray home where a 62-year-old woman died in an upstairs bedroom this morning. Firefighters said the fire load was high due to a large amount of belongings inside. Towels over a heater are a possible cause. pic.twitter.com/fZnGO4Z4Gt

— Paul Dowsley (@paul_dowsley) June 10, 2018

Fire crews entered with breathing apparatus to reach Gaye in her bedroom.

“I don’t know how the firies got up there, to be honest … [there] wasn’t any clear air in there.”

He said Gaye had been using a cane to get around. Wheelchairs were found inside the gutted home and Seven News reported she had severe osteoarthritis. Authorities could not confirm the nature of Gaye’s disabilities.

“There was a lot of furniture and household items in the house that adds to the fuel load and makes fire fighting very difficult,” MFB Commander Roger Chitty said.

It took 40 minutes for fire crews to extinguish the blaze.

Commander Chitty said it was a “major concern” to find the house had no working fire alarms.

MFB said smoke alarms should be installed on every level, and inside each bedroom where someone sleeps with the door closed.

“Heaters should be monitored at all times and kept at least a metre away from flammable items such as clothing or bedding,” MFB said in a statement on Sunday evening.

Leslie was taken to Footscray Hospital with minor injuries but left before being assessed by medical staff.

The neighbour said the two women were active in the church, and went on a lot of overseas trips and did charity work.

“They collected stuff for church charities … I think it was boxes of books and things,” he said.

-with AAP