Revellers who gathered for all-night parties at a Belfast apartment complex could "kill people", Stormont's leaders have warned.
Arlene Foster and Michelle O'Neill spoke of their shock at the photographs that appeared in this newspaper on Monday.
The images showed party-goers in a number of apartments at the Obel Tower 64 complex.
There is no suggestion that every apartment in the Donegall Quay building was involved in partying.
Police confirmed that officers removed about 40 non-residents from a number of the apartments on Saturday night over breaches of Covid-19 regulations.
The company that rents out the apartments in the Obel building has launched an investigation.
At Stormont's daily briefing on Monday, Mrs O'Neill said the gatherings were "totally unacceptable". "We're still living with this virus and for some time to come," she said. "For those people to get together in large groups like that, that is totally unacceptable. Even more so than that, that's actually killing people."
Condemning the actions of those involved, Mrs Foster said the reports had left her "shocked" and incredulous.
"I have to say that was an incredible picture to look at, the fact that people were partying," she added.
"It was almost like a nightclub scene. That is wrong and you know what, that's only going to delay the regulations from being lifted for other people."
The First Minister added: "These people are reckless and are quite possibly spreading the Covid-19 virus in Belfast. I think it was wrong and they should look to themselves and really ask themselves a question: Are they putting people's lives at risk? In my view, they are."
On Monday the PSNI faced pressure to explain why tougher action was not taken. Despite 40 people being ejected from the complex, no arrests or fines were issued, the PSNI confirmed. A spokesperson stated that enforcement is a "last resort".
As of May 1, the PSNI has issued 377 penalty notices. The PSNI was unable to provide an up-to-date figure on Monday.
The weekend incident has prompted Dream Apartments, the company which rents out the apartments, to launch an investigation, stating it "completely condemns" any breaching of social distancing regulations in the complex. A spokesperson for the firm explained the apartments are currently available to rent to key workers, as well as to those who want to self-isolate.
The company had taken the booking "in good faith", they added, in the understanding that it was helping people with the need to self-isolate.
The spokesperson criticised the "deplorable" abuse of trust.
The incident has led to calls for the PSNI to explain its handling of the matter.
Alliance MLA and Policing Board member John Blair said that when police are presented with instances of "such clear flouting", effective action needs to be taken.
"I will be taking up the matter with the Policing Board," he said. "These are very serious issues and the public who have diligently stood by social distancing practice are rightly expecting these matters to be taken seriously by all statutory authorities, including the police.
"Of course in these circumstances we have to rely on people to exercise common sense and we also need clear and consistent messaging from all government ministers and departments.
"However, such clear flouting of the law whilst there is still risk of passing on the virus to others needs to be followed up by police."
The PSNI was asked to comment.