Firefighters have extinguished a building fire in central Auckland which sent smoke billowing through Queen Street.

About 50 firefighters were called to the two-storey Whitireia building on Auckland's Queen St, closing the busy road in both directions between Mayoral Dr and Karangahape Rd, causing "traffic chaos".

Taxi driver Vinay Kumar was parked at the rank in Turner St and phoned 111 when he saw smoke coming from the building.

"I went close to observe and saw flames inside from the window. I quickly rang 111 fire department and reported the fire and I was still on phone when first fire crew came.

Big smoke on upper Queen St pic.twitter.com/wYj7pllyya

— Su Yin Khoo (@ksuyin) November 19, 2017

"By the time I hung up the building was totally engulfed with windows breaking and flames coming out with thick black smoke."

The thick smoke forced Kumar to move his car further from the scene to be safe.

Taxi driver Vinay Kumar saw the flames and called 111.

Fire area commander Richard Twomey said the fire started in a kitchen on the third floor of the centre of the building.

"It was quite well involved when we got here and it was starting to spread to the upper floors," he said.

"We have it contained at the moment it's just that the building is heavily smoke logged so we are in the mop up phase at the moment."

Twomey said there were people in the building at the time but they all got evacuated safely.

"When we arrived we were told that there was possibly people in there so we searched the buildings and luckily all the people were out."

Heavy smoke was billowing from the building. Photo / Sarah D'souza

He said there were no injuries at this stage.

"We will obviously bring our investigators in and they will do what they do to determine a cause," Twomey said.

"We have quite a lot of resources here. It was a third alarm level so there is about 15 appliances and the best part of 60 of our staff.

"I believe the building is a polytech and it is actually multi-use with restaurants and all sorts."

Twomey said: "We got in nice and quickly and the guys did a great job."

"[When we turned up] around the back there was flame that had blown out through the back windows so it looks like it may have been a bit of a flash fire that got going quite quickly.

"From the windows it spread up the back of the building and entered the other floors."

Twomey said the building would have structural damage and would be shut for some time.

"It is quite a significant fire."