Australian Prime Minister Tony Abbott said on Tuesday security officials had intercepted a heightened level of 'terrorist chatter' in the aftermath of last week's deadly Sydney cafe siege. 'The national security agencies today indicated that there has been a heightened level of terrorist chatter in the aftermath of the Martin Place siege,' Abbott told reporters in Sydney. 'That's why it's important that people remain alert.' Man Haron Monis, a self-styled sheik, held hostages in a 16-hour siege at the Lindt Chocolate Cafe in Martin Place, a central Sydney shopping and office precinct, a week ago. Two hostages and Monis were killed when police stormed the cafe.
