A digging operator who robbed a Manukau BNZ with a fake bomb was caught by "science there is no escaping from," the bank says.

Tuakau man Clive Mackintosh McKay, 47, was sentenced to six years and three months in prison today following the BNZ robbery earlier this year.

He entered the BNZ bank on the corner of Great South Road and Ronwood Avenue on January 24 and demanded money, claiming to have an explosive device which he left on a teller's desk.

McKay made off with a small amount of money, hailed a taxi to a McDonald's in Otara and was caught on the vehicle's CCTV camera.


The police bomb squad later found the device was not viable.

He was caught by a bank security measure, triggered during the robbery, which sprayed a synthetic DNA over his equipment, clothing and skin, according to the BNZ.

It was this SelectDNA which connected him directly to the robbery, BNZ head of enterprise security Owen Loeffellechner said.

The new forensic technology had been introduced to all of the bank's stores nationwide, he said, providing a "science there is no escaping from''.

"This conviction is very pleasing and helps with closure for all our staff subjected to what was a dramatic and frightening crime,'' Mr Loeffellechner said.

Victim impact statements from the bank manager and another staff member "made for disturbing reading'', Judge Charles Blackie told the Manukau District Court at McKay's sentencing today.

The robbery involved "significant planning'' and "careful thought'', Judge Blackie said.

"Quite ingenious one might say, but for the wrong purpose.''


McKay wore a black wig, drew a false tattoo on himself and applied tape to his fingers so as not to leave any fingerprints, Judge Blackie said.

He entered the bank with a plastic box about the size of a shoe box, containing batteries, a timer and electrical wiring.

It had the "overall appearance of a bomb'', Judge Blackie said.

McKay demanded $200,000 and told bank staff he would set off the device and blow up the bank if he didn't receive it because he didn't care about his life.

He received around $150 in low denomination notes.

On his arrest, police discovered a small cannabis operation at his property.

He admitted his offending and told police he needed the money for bills, as he had recently lost his job.

McKay had a "long record of criminal offending'', starting in the Youth Court in 1982, Judge Blackie said.

He had since amassed eight pages of convictions, ranging from assaults, theft, forgery, male assaults female, methamphetamine charges and threatening to kill. He had eight previous robbery and aggravated robbery convictions.

McKay also received a warning under the three strikes legislation.