Police call for man seen riding past suspicious Geelong church fire to come forward

Police have appealed for a man filmed cycling past a suspicious fire at a historic Geelong church to come forward.

The heritage-listed, 103-year-old Presbyterian church was destroyed in the fire early last Friday.

Detectives investigating the cause of the fire have been told that a man, who is a potential witness, rode a dark-coloured mountain near the scene of the fire on Pakington Street in Geelong West, and stopped to watch the blaze for a short time.

He spoke with another man, who police have since interviewed, and then rode off just after 4.30am.

Detectives have released mobile phone footage of him riding past the scene.

He is described as Caucasian, about 182cm tall, and aged about 30. At the time of the fire, he was wearing a cap underneath his bike helmet, a black and white striped shirt under a blue hoodie, shorts and fingerless gloves. He was also carrying a light yellow or cream backpack.

Police have appealed for the man or anyone who can identify him to come forward.

A church elder has told 9NEWS the community has been devastated by the loss of their beloved building.

"It’s hard to know initially what to feel - we know it’s quite a significant moment for the church," Luke McSeveny said.

Anyone with information is urged to contact Crime Stoppers on 1800 333 000.