'Heightened Level' of Terror Chatter Heard in Australia Country's terror alert hovers on 'high' after last week's siege in Sydney By Jenn Gidman, Newser Staff Posted Dec 23, 2014 7:54 AM CST 3 comments Comments In this photo released by China's Xinhua News Agency, Australian Prime Minister Tony Abbott speaks at a press conference in the Parliament House in Canberra, Australia. (AP Photo/Xinhua, Xu Haijing) (Newser) – Although the gunman who killed two hostages, then himself, at a Sydney chocolate cafe last week hasn't been officially tied to any terrorist groups, terrorist-like chatter in Australia has ramped up since last week's siege, the BBC reports. PM Tony Abbott today said that info he has received from security agencies revealed "a heightened level of chatter amongst people who we would normally think of as terrorist sympathizers." Despite this announcement and his call to the Australian people to remain vigilant and alert, Abbott added that the nation's terror alert level would remain at "high" instead of moving up to "extreme." "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. Meanwhile, hundreds attended memorial services for Tori Johnson and Katrina Dawson, the two hostages killed in Sydney.