Police out in force for Anzac ceremonies in Australia

Police Friday vowed a heavy security presence as Australia prepares to honour its war dead at Anzac Day commemorations a week after an alleged terror plot was foiled.

Security at ceremonies around the country on Saturday has been stepped up after two Melbourne teenagers were charged with conspiring to commit a terrorist act at an Anzac parade.

A 14-year-old in Britain has also been charged with inciting the purported attack and encouraging them to carry out a beheading.

Victoria state police Deputy Commissioner Lucinda Nolan said while undercover officers would be deployed, most officers would be uniformed.

"We are treating the security environment at the moment as high and we will be responding accordingly," she told reporters.

"We will have every capability to respond to any threat that we assess may be relevant. So we will have a very, very visible uniformed police presence."

However, she stressed the show of force was precautionary and there was no clear threat.

"For us, tomorrow is a day of celebration. There is no known risk. But we will be treating the event with the most appropriate capability."

In Western Australia, Police Commissioner Karl O'Callaghan said firearms would be worn to Anzac Day dawn services for the first time.

"Traditionally when officers turn up to the dawn service and march they turn up unarmed," he told ABC radio. "But unfortunately the threat level has gone up in Australia this year."

Ceremonies are held annually across the country on the April 25 anniversary of the ill-fated 1915 landing of the Australian and New Zealand Army Corps at Gallipoli in modern-day Turkey during World War I.

More than 10,000 New Zealand and Australian servicemen died in the failed eight-month campaign with Gallipoli becoming a defining symbol of courage and comradeship for the two nations.

This year's services take on added significance on the 100th anniversary with Prime Minister Tony Abbott urging people to turn out in numbers in response to the terror threat.

"The greatest act of defiance that Australians could make towards those who would do us harm is to turn up in very large numbers at Anzac Day services to show support for our country, our values and our armed forces," he said in the wake of the foiled plot. Abbott is in Turkey to mark the day.

Although no WWI soldiers survive, dawn services and marches across Australia are expected to be heavily attended by veterans, their families and the public.

Australia raised its threat level to "high" last September and has since carried out a series of counter-terrorism raids, with alarm fuelled by the departure of more than 100 of its nationals to Iraq and Syria to fight with jihadists.