Investigations into the fire's cause are beginning this afternoon.
"At this stage it's undetermined," incident controller Tony Hope said.
"We don't have leads towards [the fire being] suspicious, but we need to go through the process."
He said the damage suffered was substantial and that the building would be closed.
"There is some damage to the structure [and] the brickwork. All the ceiling is destroyed, [there is] damage to the iron on the roof.
"In the ceiling space there was pine lining boards that have all been destroyed from the fire, so it's actually reached right through to the top of the roof structure."
Members of the church community were able to enter the building once the fire was out to collect some items.
One member described the fire as heartbreaking.
The fire has been brought under control.
Roads around the scene have been blocked to traffic.
Detectives and firefighters remain on scene.
Members of the church community have also gathered.
A fire has broken out in a church in North Bendigo.
Firefighters were called to the St Paul's Coptic Orthodox church at the intersection of Bayne and Smith streets just before 1pm on Sunday.
The building has suffered significant damage.
More to come.
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