Worshippers have been forced to flee an Australian synagogue after it was set on fire in what the prime minister has condemned as an “act of hate”.

Firefighters were called to Melbourne’s Adass Israel synagogue just after 04:00 local time on Friday (17:00 GMT Thursday), finding the building fully ablaze when they arrived.

Community leaders have told local media that “a few people” were inside at the time for morning prayers, and they reported seeing firebombs thrown inside. One person was injured and fire caused extensive damage.

Police say that they believe the fire was deliberately lit but are keeping an “open mind” on motive.

In a statement, Prime Minister Anthony Albanese said the incident in Ripponlea, in the city’s south-east, was “clearly aimed at creating fear in the community”.

“This violence and intimidation and destruction at a place of worship is an outrage,” he wrote.

“I have zero tolerance for antisemitism.”

He added that he had been briefed by the Australian Federal Police, who would provide support to authorities in the state of Victoria.

“The people involved must be caught and face the full force of the law.”

Victoria Police said the exact cause of the fire had not yet been determined and an arson chemist would visit the site.

However Det Insp Chris Murray said a witness had told them two people in masks appeared to have spread accelerant inside the building.

He appealed for anyone who may have witnessed the incident, or who may have CCTV or dashcam footage from the local area, to contact police.

Synagogue board member Benjamin Klein told The Age newspaper that people inside “heard banging on the door and the window, and some liquids came through which were lit”.

“The whole thing took off pretty quickly,” he said.

Det Insp Murray – who was confronted by an angry worshipper while updating the press – said police would be committing significant resources to the investigation and increasing patrols around the area.

“We’re going to do our best to make sure that they can return, as they should, to their local synagogues, doing what is absolutely Australian – that is to be able to worship without fear.”