News: UPDATE 1-Sydney police officer who shot dead mall attacker praised for courage

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The Sydney police officer who shot dead the man behind the deadly stabbing attack at one of the city's busiest shopping malls has been identified as Inspector Amy Scott.

Inspector Scott was in the shopping centre while the attack unfolded and confronted the man after being directed towards him by onlookers, local media reported.

Police named the assailant on Sunday as Joel Cauchi, and have ruled out terror or ideology as a motive for the random attack which killed six people.

"The man allegedly lunged at the officer, before he was shot," New South Wales police said in a statement on Sunday.

Inspector Scott was shown in local media footage administering CPR on the man after he was shot.

"When I met Amy last night ... we talked about her going straight into police mode, everything she has been taught during her career and how instinctive it was," NSW Police Minister Yasmin Catley told Sky News on Sunday.

"When I said to her 'thank you for your courage' she said 'it was not just me, the bystanders around me were so helpful'. (She was) so humble, it's just typical of a NSW police officer."

Witness Jason Dickson, who saw Inspector Scott follow Cauchi, said he had written to NSW police bosses praising her actions in stopping the carnage.

"He turned around, pulled out a knife, she said put it down, he didn’t and then she pulled the trigger and then she pulled the knife away and started doing CPR on him," he told Reuters on Sunday.

"If she didn’t do it, he would’ve kept going ... she (has) done an awesome job and I’m proud of her."

NSW Police Commissioner Karen Webb said Inspector Scott would be interviewed as part of the police investigation into the attack.