The family at the centre of an engagement party that apparently breached Melbourne’s virus rules say they have had death threats since the celebration became public.

Friends of the family who hosted the event in Caulfield North have said the hosts had asked for forgiveness amid mounting criticism of the event.

“We did wrong but the hate coming our way is just so mean! So far we’re all isolating and have received negative results,” the woman said in a response seen by the ABC.

By late Monday afternoon a third COVID case had been linked to the engagement party, with Victorian authorities on high alert amid fears it might become a super-spreader event.

The party was attended by prominent members of the Victorian Jewish community, who have faced criticism from within the community for their actions.

Jewish Community Council of Victoria president Daniel Aghion said the vast majority of the community was abiding by Melbourne’s COVID restrictions and the family was regretful.

“I think it can be best described as lockdown fatigue. Somebody made a mistake and did something they shouldn’t have,” he said.

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Video circling widely purporting to be from the event shows a large group of people watching a speech in which a man jokes about coronavirus restrictions.

The man said “clearly this is legal because it’s a group therapy session”.

The group laughs at the comments. No one in the video is wearing a mask.

In a further blow to the party organisers, however, Victoria Police has signalled the event will likely also prove to be expensive, with fines of up to $350,000.

Victoria Police Commissioner Shane Patton described it as a “selfish, disappointing and outrageous” breach.

“There were 69 people in attendance in what appears to be total breach of the CHO guide lines,” he said.

He said each adult who attended would be fined $5500 – meaning up to $350,000 in fines in total.

That made for “an expensive engagement party,” Commissioner Patton said, adding that the time for discretion had come to an end, with rules to be strictly enforced.

Victorian Premier Daniel Andrews was also angry about the party, one of several rule-breaking events in Melbourne last weekend.

“It shouldn’t have happened. Some of the commentary in the video is just blatant. What makes me really angry about it is there are 69 people at that event and no matter what you’re told or what you read, the fact is there has been transmission at that event,” he said.

Mr Andrews said the party might yet become a super-spreader event.

“Our contact tracers, who are working their guts out for all of us, will have to spend literally thousands of hours dealing with hundreds and thousands of people connect to that engagement party,” he said.

“That is the work they must do but it is all entirely preventable. That is what makes me angry and disappointed.”

“By its nature, this is uniquely bad.”

Other virus rule-breaching events in Melbourne at the weekend included a pub crawl in Richmond and a street gathering in Northcote. Melburnians face much tougher COVID measures from midnight Monday as a result of the events and the continued spread of the virus across the city.