Sydney (AFP) - Australia said Friday it is upgrading security at parliament in the face of threats from extremists who are also targeting the prime minister and other leaders, after revelations Islamic State jihadists were plotting "demonstration executions" in the country.Asked about intelligence that he and other senior officials may be attacked, Prime Minister Tony Abbott said: "There is chatter, there has been chatter, amongst these networks of targeting government people."There is no doubt about that.