Leaders of the Jewish community have called for action after separate attacks on a synagogue and a restaurant in Melbourne.

An unknown man entered the grounds of the synagogue on Albert Street in East Melbourne at 8pm yesterday.

He poured flammable liquid on the front door of the religious building and set it alight before fleeing, Victoria Police said.

There were 20 people having a Shabbat dinner inside the synagogue at the time, however, everyone was able to evacuate from the back.

Fire crews were able to extinguish the blaze, which was contained to the front entrance.

Victoria Police Commander Zorka Dunstan said the arson was being treated very seriously, but it had not been declared a terrorist attack.

“At this stage, we are not declaring this a terrorist incident; we will determine the intent of the persons involved to determine if it is terrorism,” Dunstan said.

Police have released a CCTV image of a man they wish to speak to in relation to the fire

He is described as being of Caucasian descent, and aged in his mid-30s. He has a beard and long hair, and was seen wearing dark clothing.

In a separate incident, a group of 20 protestors stormed and trashed an Israeli restaurant on Hardware Street in Melbourne’s CBD.

Witnesses say the group was chanting “death to the IDF” before they arrived at the restaurant called Miznon.

Diners were fearful as the group threw food and chairs at windows and knocked over tables. 

One 28-year-old was arrested at the time and has been released, and a further investigation will follow to identify the alleged offenders.

Dunstan said the small group had peeled away from a larger protest in the CBD.

Victoria Police also revealed a third incident took place this morning, but they have not linked the three separate attacks – it is not clear whether the third attack was an anti-Semitic motivated attack.

In the third incident, a group of men entered the premises of a business on Para Road in Greensborough at 4.30am.

The group set fire to three cars and used spray paint to vandalise the vehicles and a wall of the business.

Police said they have not confirmed an anti-Semitic motive for the attack on the business; however, Dunstan said they alerted the press to the incident because they had “been subject to pro-Palestinian activity” in the last 12 months.

She clarified there were no previous criminal attacks on the building, but rather protest activity surrounding the business. 

“Investigators across all three incidents are liaising with counter terrorism to understand if there are any links,” Dunstan said.

“At this stage we are not aware of any links, but we are not discounting it.”

Police have not linked the two.

Executive Council of Australian Jewry co-chief executive Alex Ryvchin called the attacks “a severe escalation directed towards our community”.

“We urge all sides of politics and all Australians to condemn these deplorable crimes,” he said in a statement.

“Those who chant for death are not peace activists.

“Those who would burn houses of prayer with families inside do not seek an end to war.

“Those responsible cannot be reasoned with or appeased.

“They must be confronted with the full force of the law.”

Melbourne’s Lord Mayor Nicholas Reece called the attack “shocking.”

”These are absolutely shocking, unspeakable acts of cowards,” Reece told Today.

“I cannot condemn this sort of behaviour in stronger terms… this is a city of peace and tolerance, and we will not stand for this.

“This goes against everything that we stand for.”

The Lord Mayor also said the group were sharing a meal when a young boy inside the synagogue alerted everyone to the fire. 

Reece said police are gathering CCTV footage of the area and he is “confident” that they will catch the offender.

“I hope that we throw the absolute book at them… this is racism, this is anti-Semitic racism,” he said.

“To target a Jewish place of faith on the Sabbath, there’s people inside having a meal, to try to burn it to the ground…is there a more despicable act that you can think of in a busy city?” 

Investigators are working to find a motive for the arson attack.