AFP

The Australian government has vowed to push through plans for a fire warning system, as authorities say some of the fires that ravaged the state of Victoria last week, and killed at least 181 people, were the result of arson.

More than 400 fires erupted in the state destroying scores of houses, leaving some 5,000 people homeless, and scorching 2,850sq km of land.

Australian police were questioning a man on Friday over one of the bushfires, and according to local media, he was expected to be charged with arson causing death.

"Police are currently speaking to someone over the Churchill fire," a police spokesman told the Associated Press.

At least 21 people died in the town of Churchill, located 140km southeast of Melbourne, the state capital.

Meanwhile police have released two men who had been detained on Thursday after they were reported by local resident of acting suspiciously in an area burned out by fires.

'Stalled' warning system

A national warning system aimed at alerting rural resident of a potential bushfire, has been stalled by privacy laws and disagreements between state officials over funding for years.

Robert McClelland, the attorney-general, said a plan for a telephone alert system had been before the government since 2004, but that state governments had not endorsed it and that changes were required to federal privacy laws that prohibit private numbers from being handed out.

McClelland said he backs sending a barrage of automated warnings to all phones in an area where there is an emergency.

He also said another reason the system had not been implemented was because officials had to be sure it would not crash communications systems used by emergency services.

Bruce Esplin, head of the Victorian Emergency Services, said a national warning system for fires, floods and potential terrorist attacks was overdue.

"I think it's taken too long,'' he told the Associated Press.

"I think we need to work as a country, not as separate states and territories, and it's time we did that."

Fires still raging

Thousands of mostly volunteer firefighters were still battling more than a dozen fires across the state Thursday, a day after some residents of scorched towns were allowed returned home.

A government official says the number of homes destroyed in Australia's deadliest wildfire disaster has jumped by hundreds to more than 1,800.

The previous number of homes lost when fires ripped across a swath of southeastern Victoria state was a little more than 1,000.

Victoria state Emergency Services Commissioner Bruce Esplin said Friday the number of homes destroyed in the wildfires now stands at 1,831.

Arson specialists say they have concluded that the fires had six separate sources, four of which were not suspicious.

Foul play was suspected in the fire that destroyed Marysville and they are convinced another deadly fire, known as the Churchill fire, was arson.

Wildfire arson carries a maximum penalty of 25 years in prison, but authorities have said they will bring murder charges if they can.

A murder conviction carries a maximum life sentence.