SYDNEY - Australian Prime Minister Tony Abbott yesterday warned of heightened "terrorist chatter" in the aftermath of the fatal Sydney cafe siege and said that another attack was likely, as tearful mourners paid tribute to the victims.
Iranian-born gunman Man Haron Monis, who had a history of extremism and violence, took 17 hostages in the city's financial heartland on Dec 15, unveiling an Islamic flag and demanding to talk to Mr Abbott.
He was killed as armed police officers stormed the eatery after 16 hours. Two hostages also died - mother-of-three Katrina Dawson, 38, and 34-year-old Lindt cafe manager Tori Johnson - while several were injured.
"A briefing from the security agencies today indicated that there has been a heightened level of terrorist chatter in the aftermath of the Martin Place siege," Mr Abbott said after a meeting of his National Security Committee.
"That's why it's important that people remain alert and aware, as well as reassured that our police and security agencies are doing everything they humanly can to keep us safe."
He did not raise Australia's terror alert level beyond its current high, which means an attack is likely. An extreme alert level means one is imminent or has occurred.
"I am alerting people to the fact that the terror threat remains high and, as you all understand, at this level, an attack is likely," he said.
The police have said they would be boosting their presence at prominent locations such as Sydney Harbour, home to the Opera House, over the Christmas period.
Australia raised its threat level to high in September, when it carried out a series of counter-terrorism raids across Sydney and Brisbane following a flow of its nationals to Iraq and Syria to fight with the Islamic State of Iraq and Syria group and other militants.
Mr Abbott's warning comes as emotions remain raw over the siege, which triggered an outpouring of grief and shock in the country.
Yesterday, NSW Premier Mike Baird raised the possibility of a permanent memorial being raised to honour the two victims.
A private funeral was held yesterday for Mr Johnson - hailed as a hero after reportedly trying to wrest the gun from Monis - with hundreds of tearful mourners in attendance at St Stephen's Uniting Church, just metres from where he died. Several of the hostages also attended.
The service emphasised unity after the attack, with the Johnson family using a phrase by Persian poet Rumi on the front page of the order of service which read: "Out beyond ideas of wrong-doing and right-doing, there is a field. I will meet you there."
A memorial for Ms Dawson also took place at Sydney University, her alma mater, with up to 1,000 mourners, including Mr Abbott.
In emotional speeches, her family and friends fought back tears as they spoke of her intelligence, generous spirit and deep love for her children, aged four, six and eight.
"She was destined to change the world, just not the way it's happened," said her older brother Sandy Dawson.
Mr Abbott has ordered an urgent inquiry into the circumstances surrounding the siege.
NSW state opposition leader John Robertson resigned after coming under pressure when it was revealed that he had signed a letter to support Monis gaining access to his children in a dispute with his second wife.