An explosion which rocked West Auckland last night and killed one person was a welding accident involving a father of two young children, a person close to the family says.

On Monday evening the explosion rattled the suburb of Henderson, with the windows of neighbouring properties shattering on Universal Dr and Don Buck Rd.

The Herald has spoken to a woman who knows the occupants of the Don Buck Road house personally.

She said the person killed in the explosion was a father of two school-aged children.

The explosion was not drug-related as many people had wrongly claimed on social media.

Lower Don Buck Rd superette co-owner Kanchun Chauhan said she was working at the shop when she heard a massive thud and the entire building was shaken.

There was not any damage to her property.

She said after the explosion police cars had cordoned off Don Buck Rd and Universal Dr.

"I've never seen so many people. What we saw was the back end, we saw the back of their backyard which connects to another house."

It was a shed that had exploded, she said.

"A lot of the locals think it is a P lab, but we found out it was a shed that a guy was welding in.

"The sparks must have exploded, there were paints and solvents as well."

One customer told her he had known the man and knew he was a welder who often worked in the shed.

People had come from all around, and had walked and driven "in droves" to see what the source of the explosion, Chauhan said.

"The impact was pretty immense, it was a massive thud. The smoke that billowed up was pretty big.

"The atmosphere and the smell was tainted."

At 7.30am a fire investigator had arrived at the scene to continue the investigation, a Fire and Emergency New Zealand spokesman said.

A guard was on scene overnight.

Last night residents described how the deadly explosion shattered neighbours' windows and left some residents' eyes stinging.

The force shook nearby homes and blew out neighbouring windows. Debris from the explosion landed in a tree.

A black plume of smoke could be seen drifting from the property on the corner of Don Buck Rd and Universal Dr.

Paul Eutnam, at Lower Don Buck Rd Superette, said his first thought when he heard the loud explosion, which happened about 10m from the shop, was that there had been a terrorist attack.

"We've got a solid concrete building here and we could feel the jitter and shakes ... It was very loud.

"I thought there was a local terrorist attack of some sort. My first comparison was what it would be like in 9/11 in New York. That's what it was like - a sudden big bang out of nowhere."

Eutnam said plumes of black smoke erupted into the air followed by white smoke.

Residents gathered in the superette and were reporting a slight irritation of their eyes and nose.

"There was a distinctive smell along with some allergic reactions. It caused quite a commotion. There was a bit of an audience here for about two hours."

Residents were unable to enter their properties and were asked to park outside the shop. The explosion had shattered neighbours' windows and also scared their pets, he said.

Eutnam said the explosion appeared to have happened in a garden shed in the backyard of the property on Universal Dr, but the explosion left a massive hole in the next door neighbour's fence.

He said from Don Buck Rd he could see pieces of corrugated iron from the shed scattered over a 5m tall tree.

Several other residents felt the force of the bang.

A neighbour said the impact felt as if a large shipping container had been dropped on the ground from a big height.

She said it blew out neighbouring windows and black smoke could be seen billowing into the sky.

A resident said the explosion happened near the roundabout on Don Buck Rd and a fire truck was parked up outside the address. Police cars were also present.

A St John spokeswoman said they were called to the scene at 4.54pm and one ambulance and two support cars arrived four minutes later.

The spokeswoman said they did not treat anyone and left the scene at 6.15pm.