Image copyright EPA Image caption The fire has focussed attention on the city's homeless problem

A 52-year-old man has been arrested after three people died in a fire at an abandoned factory in Melbourne, Australia.

Firefighters were called at around 23:30 (12:30 GMT) on Wednesday, after reports of an explosion.

It took them 40 minutes to extinguish the blaze, before finding three bodies, reported to be two men and a woman.

The factory was often used as a shelter by homeless people.

The dead people are also believed to have been homeless, Australian media reported.

Victoria Police say they are investigating the cause of the fire, which they are treating as suspicious, and that the arrested man is "assisting investigators with their enquiries".

Image copyright 9News.com.au Image caption Police said the cause of the fire remains under investigation

One witness, taxi driver Mohamed Ali, said he had heard screams coming from the factory in Footscray, a few kilometres west of the city centre.

"A few minutes later I saw the fire engines come," he told the Australian Broadcasting Corp.

"For me, it's a horrible situation because we couldn't help. I haven't seen anything like this in my whole life. I'm not feeling good."

Image copyright 9News.com.au Image caption Firefighters fought the blaze in Melbourne for 40 minutes

Prominent Melbourne youth worker Les Twentyman said homeless people often took refuge at the site.

"There is a little alcove near the car park - people sleep in that little alcove," he told the Herald Sun.

"It just shows how desperate they are."

The site was originally Victoria's largest ropeworks and operated from 1903 to 2002. After the factory shut, the state government backed plans to build a large apartment complex on the site.