It was the popping sound of exploding windows that woke Father Andrew Matthew at 2am to the destruction of St Mary’s Church.

At first, the Catholic priest in the Auckland suburb of Avondale said he thought workers at a construction site had started early.

But as he roused from sleep this morning, that crackling noise carried far worse news.

“When I looked out the window all I could see was a sea of red flames. It’s a real shock,” he said.

Matthew rang 111 as he walked out into the car park for the church and its neighbouring St Mary’s Catholic School on Great North Rd.

“Our poor church was on fire. All I could do was watch and pray.”

Even at that stage, Matthew could see the church was lost.

Standing in the car park, the burning church radiated heat a considerable distance as roofing iron buckled and brick walls collapsed.

Parishioners hugged and cried in the car park in front of the smouldering wreckage in the late morning.

While too early to make firm decisions, Matthew said it likely the parish would combine with another parish while decisions on replacing the church were made.

He said the thriving parish had about 300 people attending each of three Sunday services.

Auckland Catholic Diocese general manager James van Schie, also at the church this morning, said the parish was established in 1921 and the church built in the late 1950s.

“For over 100 years, it’s been a vital part of the fabric of the Avondale community,” he said.

“There are so many Aucklanders who trace their family history here; baptisms, funerals, weddings. It is a vibrant parish.”

The fire has gutted the Avondale church. Photo / Andrew Matthew.

Firefighters have contained a blaze at St Mary’s Catholic Church on Great North Rd in Avondale.Photo / Hayden Woodward

Van Schie said he wanted to thank Fire and Emergency for responding so quickly.

“It’s completely hollowed out. You know, it is a solid structure that was built in the late 1950s, but the brickwork has collapsed, the roof has melted, and it has been completely hollowed out.”

He said parents at the school were asked to keep children home today on what was supposed to be their first day back after the holidays.

“Our priority today is making sure the site is safe.”

Van Schie said the hundreds of parishioners who attended the weekend services would be “devastated”.

Eight fire trucks were sent to the scene at the fire's peak. Photo / Michael Craig.

Fire and Emergency Assistant Commander Phil Larcomb said they were called to Great North Rd just after 4am today, where the brick St Mary’s Catholic Church, in front of St Mary’s School, was on fire and had been “severely damaged”.

“Due to the nature of the weather at the moment, it’s very foggy, it’s very hard to see what’s going on, but the fire is now contained and extinguished,” Larcomb said.

At the peak of the blaze, eight fire trucks were on the scene.

Police said they will work with fire investigators to establish the circumstances of the fire.

All of the windows in the church have been blown out. Photo / Michael Craig.