A police spokesperson said a guard would be at the scene overnight and police will recommence investigations tomorrow morning.
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 asking 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 Drive, 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.
Black smoke billowing into the sky after an explosion in West Auckland this afternoon. Photo / Jo Rule
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.
Universal drive in West Auckland blocked after today's fatal explosion. Photo / Megan Harvey
Traffic was banked up about 1km along the road as police had blocked off Universal Drive and Fire and Emergency crew were redirecting traffic.
Herald reader Louise Martin commented online: "Sounded like a massive gunshot - or cannon - with a hell of a vibration."
