Canberra church destroyed by fire

A suspicious blaze has completely destroyed a Canberra church, with firefighters mopping up and checking for spotfires while police search for witnesses.

The intense fire ripped through the Tuggeranong Baptist Church in Kambah just after 6am on Saturday, with crews managing to contain the blaze and stop it spreading to neighbouring properties within an hour.

Some firies gained access to a small area inside the church by about 9am after the fast-moving blaze was brought under control, but most remained outside the building working to put out the flames.

Crews were forced to stay away from the main part of the church while the structural integrity of a large slab of roof was assessed.

The building has been destroyed and a structural engineer called in to complete a detailed assessment.

The cause of the fire will be investigated but is being treated as suspicious, with detectives on the scene.

"Police ask that anyone who may have witnessed this incident, or who may have information about the fire, to contact Crime Stoppers," an ACT Police spokesperson said.