As a knife-wielding psychotic killer stalked his way through a busy shopping centre, most people fled.

But some shoppers reached for their smartphones and hit “record”, something a high-ranking anti-terrorism police officer hopes to never see again.

Chief Inspector Colin Green on Thursday said the public did not know how to react to an armed offender in a crowded space.

Under questioning, he agreed he had been left “troubled” by not being contacted about the serious incident.

An officer explained in court that someone could have been dispatched to quickly acquire ballistic helmets and vests from a central storage and deliver them to the team on the ground more swiftly.

However, he noted, paramedics present at the mall experienced a 16-minute delay as they awaited NSW Police’s approval to utilize the personal protective equipment available there.

Furthermore, due to staffing shortages and an increased risk of beach incidents because of favorable weather conditions, no special operations paramedics were assigned to work with the NSW Police Tactical Operations Unit on the day of the attack.

Cauchi stabbed 16 people within five minutes in the shopping centre before being shot dead by police Inspector Amy Scott.

Dawn Singleton, 25, Faraz Tahir, 30, Ashlee Good, 38, Jade Young, 47, Pikria Darchia, 55, and Yixuan Cheng, 27, were killed.

He had been diagnosed with schizophrenia as a teenager and was successfully treated until 2019 when he stopped his medication, the inquest was previously told.

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