Key Points:

Don Wilkinson told friends only that he worked in "security".

In fact, he was a highly skilled policeman who had previously worked in war-torn Bosnia - an officer working in a secret and specialised team that carried out "difficult and dangerous" operations.

It was during one of those operations early yesterday that the 46-year-old from Waimauku just northwest of Auckland became the 28th NZ police officer to die in the line of duty.

His death came during what police say was a "routine" job - something the sergeant had done countless times in his nine-year policing career.

Mr Wilkinson and another officer were planting equipment on a car as part of a drug operation.

Although it was routine, police say by its very nature the world of covert operations is dangerous.

The men were unarmed and didn't have bullet-proof vests. The man who survived - whose name has been suppressed by a judge - was wearing stab-resistant body armour.

However, armed back-up was just one block away.

They were targeting a property they believed had links to P when things went horribly wrong.

It was just after 1.30am when Mr Wilkinson and the other officer were spotted by the occupants of the house while putting a tracking device on a car in Hain Ave, Mangere.

Two men emerged and disrupted their plans.

Avoiding confrontation, the policemen sprinted off.

They radioed for help but got just 75m away into Earlsworth Rd when they were caught by the two men, who had chased them in a car.

Moments later, Sergeant Wilkinson was shot dead by a single gunshot wound to his upper chest and his colleague was bashed and shot several times. He remained in Middlemore Hospital last night.

One resident heard what she said sounded like a "car blowing up". Others were woken by gunshots followed by the screeching of car tyres.

Sam Aiono heard two shots and when he came out of his house about 2.30am, saw Mr Wilkinson's body on his driveway.

"It happened out on the street but the body ended up on our driveway. We saw him lying on the ground, covered up ... The police were there. We had to walk around [the body]."

Despite the noise, the small group of armed officers standing only a block away never made it to help. Police said yesterday those officers did not hear the gunshots and everything unfolded too quickly for them to react.

When they arrived seconds later, they found Mr Wilkinson dead and the other officer badly injured.

Later, back at the suspected drug house, police found the two men they allege shot the policemen.

"Clearly it's an absolute tragedy for us to lose an officer and have another seriously threatened," said Superintendent Ted Cox, head of the Auckland metropolitan crime and operations support unit.

"If we knew there were weapons in the house, we would have approached it entirely differently."

Mr Wilkinson had spent most of his nine years with police working under Mr Cox in the technical support unit.

Those who knew Mr Wilkinson, who was single, say he was "exceptionally good at the job he did".

"I know he'd been [in the unit] for a long time because I've had dealings with him for a number of years," said Counties Manukau field crime manager Detective Inspector Mark Gutry.

"He was a hard-working and dedicated officer."

Mr Wilkinson served overseas, in Bosnia, before joining the police, although it's not clear if his background is with the Army or a private security-type company.