SYDNEY — A teenager was charged with plotting a terrorist attack on an Australian veteran's day ceremony, police said Monday, the second year in a row authorities say they have thwarted an attack linked to the national holiday.

The 16-year-old boy was charged with one count of planning a terrorist act after being arrested at his home in western Sydney on Sunday, one day before Australians across the country gathered at ceremonies to mark Anzac Day. The annual holiday commemorates the April 25, 1915, Gallipoli landings in Turkey — the first major military action fought by the Australian and New Zealand Army Corps during World War I.

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Police believe the teen was acting alone, and he had previously been on authorities' radar, New South Wales Police Commissioner Andrew Scipione said. The teen's home was searched, but Scipione declined to say if anything was seized. He would not release any other details.

In court documents, police accuse the teenager of trying to get a gun over the weekend as part of the alleged plot. His case was adjourned until Tuesday. He could face a maximum sentence of life in prison if convicted.

This is the second year in a row that police say they have stopped an attack on an Anzac Day ceremony. Last year, police in Melbourne arrested five teenagers on suspicion of plotting an Islamic State group-inspired attack intended to coincide with the city's Anzac service.

The age of the Sydney suspect was troubling but unsurprising, Justice Minister Michael Keenan said.

"Unfortunately, this is part of a pattern that we have been observing, where younger and younger people are targeted and incited to go and commit an act of terror," Keenan told reporters in Perth.

Australia's government raised the country's terror threat level in 2014 in response to the domestic threat posed by supporters of the Islamic State group. Police have since conducted dozens of raids they say have been aimed at thwarting multiple plots in Australia, including an alleged plan to attack government buildings and a naval base in Sydney.

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