Mask-wearing arsonists set Melbourne synagogue ablaze

Mask-wearing arsonists set a synagogue ablaze in a pre-dawn attack on Dec 6 in Melbourne, the police said, sparking condemnation by the Australian Prime Minister.

The police said there was "significant damage" to the building, and television images showed firefighters hosing down the embers through the door.

A witness entering the Australian synagogue for morning prayers saw "two individuals wearing masks", Detective Inspector Chris Murray of the Victorian police arson and explosive squad told reporters at the scene.

"They appeared to be spreading an accelerant of some type on the premises," he said.

The synagogue was "engulfed in flames", he added.

"We believe it was deliberate. We believe it has been targeted. What we don't know is why."

The police will increase patrols and do their utmost to catch the arsonists, who were described as wearing dark clothing, he said.

Detectives would be looking at CCTV footage and interviewing any witnesses, Mr Murray said.