Prime Minister Tony Abbott has played down reports a young man shot dead by police in Melbourne had made terrorist threats against him.
Terror suspect Numan Haider, 18, was fatally shot outside Endeavour Hills police station after attacking two police officers on Tuesday night.
Media has reported the teenager made specific threats against the prime minister, but Mr Abbott has rejected the claim.
"I haven't been officially briefed to that effect, so I'd rather not further comment on it," he told reporters in New York, moments after addressing the United Nations Security Council on the threat of foreign fighters.
Mr Abbott described Tuesday's stabbing attack on the Australian Federal Police officer and Victoria Police officer as an "ugly incident", but assured Australians the government would be vigilant at home and abroad.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
However, he highlighted the threat posed by those travelling to Iraq and Syria to fight with extremists groups such as Islamic State.
He said there were at least 60 Australians now fighting with ISIL and other terrorist groups in the Middle East, while "well over" 20 known to have been involved in the conflict had returned home.
The government had also cancelled more than 60 passports, including that of Haider.
Pointing to the brutal 2013 attack on British soldier Lee Rigby, who was hacked to death on a London street by two Islamic extremists, he said all that was needed to commit an act of terrorism was a knife, a smartphone and a victim.
"These are quite significant numbers," he said of the Australians with links to the terror groups.
"Because as we've seen it only takes one or two people to commit a brutal terrorist atrocity."
