Chief executive of the trust Cate Kearney said the threats were "serious" and they had received about 40 or 50 calls.
"It is disappointing, our team work incredibly hard to support our tenants. We made a mistake this week, we know that, and we've worked so hard to make it right. And now for us to be threatened, it's not okay."
A police spokesperson said officers were sent to the Kilmore St address after a person called in, threatening another person.
Officers were called to the building at 10.45am but have since left, he said.
Police are investigating the incident and the lockdown was lifted by 12.30pm.
Meanwhile, thousands of people have since signed a petition to pressure the trust, which owns the property, to reimburse Wang for her destroyed garden.
The trust has apologised for not giving the 80-year-old a heads up but said it had to be done.
They confirmed she wasn't given a heads-up before the digger arrived but said the problem stems back to 2017.
Tenancy operations manager Martin Pearce said tenants complained about the size of the garden, saying it was in the way of a communal washing line.
He said the trust warned Wang the area would be turned into grass.