Security is being stepped up in major cities of Australia in the wake of a series of terrorist attacks on London, despite Australia's terror alert level remains at medium.
More than 50 people died and some 700, including eight Australians, were injured in four coordinated blasts targeting London's public transport system on Thursday.
It is believed the attacks were carried out to coincide with the Group of Eight summit under way in Scotland.
As Australian experts warn people that an attack on Australian soil is inevitable, security was beefed up with increased patrols and surveillance of public transport system of Sydney, Australia's biggest city and capital of the state of New South Wales (NSW).
NSW Premier Bob Carr said the attack served as a warning to Australia and that details of a city-wide evacuation plan, which is directed at dealing with an emergency akin to London's, would be announced next month.
Police have intensified their presence at possible terrorist targets in the state of Queensland.
Although Queensland Police Commissioner Bob Atkinson would not give details, he said in some areas of the state, "there is an increased police presence."
Security has also been increased at main transport hub in Perth, capital of the state of Western Australia, with armed police officers being stationed at the city's central train station.
The anti-terrorism arrangements for next year's Commonwealth Games in Melbourne, capital of the state of Victoria, are being reassessed in the wake of the bombings.
Meanwhile, Australian leaders condemned the attacks, with Prime Minister John Howard vowing the attacks "will not alter the attitude of the government of Australia towards terrorism and towards the commitments we have with our American, British and other friends to Iraq and Afghanistan."
Federal Opposition Leader Kim Beazley described the attacks as "cowardly," saying, "These terrorists are sub-human filth and must be captured and eliminated."
Australia's Islamic spiritual leader Sheikh Taj Aldin Alhilali has also condemned the bombings, calling "East and West" to "work together" against terrorism.
The Australian government has said it will help Britain in any way it can, offering to send federal police officers to London to help investigate the bombings and identify bodies.