SYDNEY (AFP) -- Australian police said Friday that a man shot dead at a Sydney petrol station was believed to be the fourth victim of a "blood feud" blamed on warring Lebanese families that has heightened racial tensions in the city.

Police said 25-year-old Ahmad Fahda was shot by a balaclava-wearing gunman mid-afternoon Thursday as he was filling up his car in Sydney's ethnically-diverse southwestern suburbs.

It follows the deaths of a man and a woman nearby on October 14, when the house they were staying in was peppered with more than 100 bullets during a nighttime drive-by attack.

Six weeks earlier a man linked to the other victims was gunned down after visiting his mosque. Two other non-fatal shootings and numerous assaults have been blamed on the feud.

As politicians and media clamored for the killers' capture, New South Wales state police commissioner Ken Moroney acknowledged the shootings had put Sydney residents on edge.

"They are creating anger, anguish and uncertainty and that in itself is a form of mental rape," Moroney told commercial radio.

Media reports have said the feud was sparked by a bitter divorce between a couple of Lebanese origin, although police believe it also has elements of a turf war between organized crime gangs.

NSW Premier Bob Carr promised to give police extra powers if need be and repeated earlier comments that those responsible would be caught.

After the October 14 double murder, Carr was accused of racism when he said Australia would not tolerate blood feuds and those who wished to pursue them were not welcome. "My message is simple: obey the law in Australia or ship out of Australia," Carr said at the time. "We're not going to see, step by step, our civilization dragged back to medieval standards of revenge cycles. Simple as that."

***The Daily Telegraph*** said after the latest killing "Sydney has had enough".

With a front-page headline of "How Dare You Do This to Our City" the newspaper said the shootings had led to wrong-headed generalizations about Australia's Arabic community.

It said the killers were a hard core of individuals with no respect for the law.

Egyptian-born Sheik Taj Aldin Alhilali, 62, described the violence as sickening.

"There is no room for this in our society," he said.