A large fire is raging in the sports pavilion at Northcote College on Auckland’s North Shore as firefighters take industrial action.

Fire and Emergency said crews were alerted to a fire at the college at 12.17pm today.

They said the Silverdale Fire Brigade was the first crew to arrive at the scene at 12.29pm.

Northcote College confirmed in a social media post that the active fire was affecting its sports pavilion.

It said students had been evacuated and were safe at another end of the campus.

“School is closing for the day at 2pm. Some students may not have their bag because of the evacuation. We are asking students to go home, if they can, without their bag.”

A fire has broken out at Northcote College in Auckland amid the firefighters' strike. Photo / Dean Purcell 

Students unable to leave at that time are being supported by staff in the school hall.

The college said an email would be sent later today to all students and whānau with further information about the fire.

A video taken from the school’s field shows large flames shooting from the burning block and plumes of black smoke billowing into the air.

The building has been engulfed in flames. Photo / Dean Purcell

A Herald reporter at the scene said bits of the building’s facade were falling away, while the central part of the roof had caved in.

A Northcote College student told the Herald the fire alarm went off and all students were evacuated to the courts. 

Flames could be seen shooting from Northcote College's gym. 

The student said everyone could see “heaps of smoke” coming out of the building as they left their classrooms. All students were gathered on the courts watching fire crews battle the blaze.

The smoke was changing from black to white and was rising “really high” in the air.

Before the smoke turned black, the student could see flames inside the building.

“Giant flames” could be seen all over the roof, the student told the Herald.

Photo / Dean Purcell 

Witness Leo Straight described the scene as “pretty hectic”, saying those gathered on the courts could feel the heat from the fire on the other side of the field.

It took firefighters about 30 minutes to arrive at the school, he said.

The fire at Northcote College can be seen from the Auckland Harbour Bridge as it continues to burn with just one crew fighting the blaze. 

Police have blocked off access to the school entrance on Kauri Glen Rd.

A spokesperson said they were alerted to the fire at 12.35pm and were assisting Fire and Emergency.

One nearby Seaview resident told the Herald she saw a plume of smoke rising from the direction of the school.

She looked online and saw there was a fire, so decided to take a look because her granddaughter attended the college.

A maintenance worker at the school said he and his team had come back from lunch to see smoke rising.

He was concerned it might have been in one of the new buildings they were working on, but thought that the safety features in them would have stopped a fire quickly.

His and his team’s cars were blocked in by emergency services, so they would not be able to leave any time soon.

The latest fire comes nearly 12 years after a devastating fire destroyed Northcote College’s technology block (E block) in September 2014.

Earlier today, the New Zealand Professional Firefighters Union (NZPFU) confirmed in a social media post that it would be striking from between midday and 1pm.

“FENZ management is quick to say that firefighters are ‘gambling with public safety’ by striking. The truth is, FENZ is gambling with your safety every single day,” the post read.

The union said another one-hour strike was planned for next Monday.

The college blaze is the second major fire to break out during firefighters’ strike action.

Last month, a fire engulfed a family-owned grocery store in Pakuranga while firefighters were on strike.

Fire and Emergency said it took volunteer crews 30 minutes to travel to the scene, compared with the usual time of about seven minutes.

It accused the union then of “gambling with the public’s safety”.

The union responded, saying it was “disgusting” that Fire and Emergency was “throwing stones at a moment when, obviously, the building is still on fire”.