Fifty police officers have been injured in Australia in a riot sparked by the death of an aboriginal teenager. A railway station was torched and the police were attacked with petrol bombs, fireworks and rocks. Four people have been arrested.

Sunday's ugly fighting in Sydney, Australia's biggest city, is a major setback for race relations.

Dozens of police officers were injured, some suffering broken legs and arms during a nine-hour confrontation in the city's Redfern district. They were attacked with firebombs and paving slabs, and had burning rubbish bins thrown at them. Shops, trains and passing cars were also targeted. Redfern's railway station was set on fire.

Police reinforcements were called in from across Sydney to help contain about one hundred rioters.

The riot was touched off by area residents, angry over the death of 17-year-old Thomas Hickey, who died Sunday after being impaled on a metal fence when he fell off his bicycle. Many youths in the predominately aboriginal neighborhood blamed the police for the death.

The authorities have strongly denied claims that the police were chasing the aboriginal teenager when he fell from his bike.

Police commander Bob Waites says his officers were not to blame for the accident. "The reality of it is that the police were patrolling, the young lad went past them," he says. "They continued on in their patrol but he for some reason accelerated on his push-bike and lost control of his bike."

Redfern is a predominantly black neighborhood. Relations with the mainly white police force have been uneasy at the best of times.

One rioter, her face hidden by a mask, says there is a dangerous level of anger within the indigenous community. "If I have to lead my people and these kids toward death - to die for what they believe in - I will do it."

Opposition politicians say the unrest was the result of years of neglect by the state government. They claim the government has ignored the problems of unemployment and poor health care as well as alcohol and drug abuse among the aboriginal community.

There will be three investigations into Redfern's night of chaos, by the coroner, an independent public affairs watchdog and the police.

Australia's aborigines are the most disadvantaged group in the country.

They die on average 20 years younger than whites and are far more likely to be out of work, in jail or suffering preventable illnesses than anyone else.

The reasons are complex. They are - in part - historical and are often related to poverty and a widespread dependency of welfare payments.