Fire crews are responding to a blaze in the Auckland suburb of Pt Chevalier early this morning - with plumes of black smoke being seen from the motorway.
Three fire appliances have been sent to the scene, which was first reported about 7.15am.
Fire and Emergency NZ said they received "multiple reports" of the early morning blaze.
The building was "well involved" when firefighters arrived, FENZ said.
A West Harbour resident was heading into the city when he spotted the smoke just after the Avondale turn-off.
"I was just driving along the motorway and saw a column of smoke. You could see it from miles away".
The man said traffic was fairly normal at that point - busy, but not anything different from the usual Friday morning commute.
It was only later on, when he checked the traffic alerts, he saw that congestion was now building in the area around Great North Road and Pt Chevalier Rd.
Auckland Transport has issued an alert to local motorists to avoid the area or to expect delays.
The roads affected include the intersection around Great North Road, Pt Chevalier Rd and Carrington Rd and the eastbound/northbound corner of Great North Rd and Pt Chevalier Rd.
By about 8.15am, the fire was under control, authorities said.